I suppose if you view it through the lens of 'I could choose any of these roles for myself based on whatever deck I would to build' then it could be construed as restricting player choice. But I don't think that ever would have been the case. 
If you view it as 'oh now I have the opportunity to splash more cards/provinces and get some fate based on how I play' then it's not restrictive at all and does allow for more flexibility. But I think starting from the viewpoint that the game would've been designed so that any player could pick any role at any time isn't likely. I doubt they would have included a mechanic like that. 

She's a Shosuro Actress, so I really like this mechanic as a way of representing their ability to mimic people.

They should spoil Tsuruchi in the same way - posting his card on Hotaru's link!

Spoiling the scorp cards by sneaking them into other articles is just so perfectly scorpion - I love it!

To be honest, I think this is kind of what makes the choice of role card so cool.  Like, the game hasn't even released yet and we're all worked up over someone that may or may not choose the role we like, and which may or may not have a significant effect.  
The idea that player decisions within the game can cause this much of a reaction, and carry this much weight is part of what makes L5R so cool!  A game driven by player interaction - BOOM, here we go! 

Can we all take a step back here.  I mean we should probably realize that this meta that is supposedly being upset by the role cards, literally has not formed yet.  No one outside of FFG has played a game with all of the cards of available to them.
So maybe lets see how things play out in the real world before we condemn or praise that one clan has access to a card that another does not. 

Spoiling the scorp cards by sneaking them into other articles is just so perfectly scorpion - I love it!

If the kimono ain't on the floor then she needs to find the door.
Cuz she's wearing it wrong.
I'm pretty sure that is a Sorpion clan saying......kind of like "a Lannister always pays their debts."
 

Spoiling the scorp cards by sneaking them into other articles is just so perfectly scorpion - I love it!

Nothing states that the card you take control of necessarily leaves play.  Good Omen or Reprieve could combo to keep the act going.  I hope I can steal something awesome like Serene Warrior, Doji Challenger, or Raitsugu or something lol

The ability to wear a Kimono properly is inversely relative to the standing of the character in the Scorpion hierarchy.
This character being sac'd for their ability is directly relevant to being such a conservative dresser.

Speaking of sacrifice tech I have no idea if it was intentional but it was snuck into the Crab card spoilers replacing the link for Hida Tomonatsu. If that was an intended reference I've gotta give credit to whoever thought up that one.

Well, someone has to say it, but congrats on the scorpion for finally wearing a kimono properly.
But yeah, she's good, and kind of scary. "I'll pull your spirit caller, thank you."

Their spots would be filled by a whole horde of Shadowlands loyalists.
Pun intended

Not Spiritcaller level good, but very close.
I could see her being a common purchase with zero fate just to run her in a political conflict and then sacrifice her after she served her purpose.

My role isn't printed on any of those cards.  
They don't make a "your characters are shadowlands" role ..........yet.

They change just enough to be meaningful.
On monday, we did not even know about this at all and were not complaining about things being restricting. I am missing how learning about a new card type with 0 downsides is now super restricting, just because it doesn't exactly match your expectations.

Roles were never supposed to be your choice. They are just a meta shift from year to year - something that is much needed in living card games which tend to become very very stale. 
If it helps you, think about it as an errata that comes out every year to shake up the best decks in the meta. This is essentialy what happens in netrunner or even mtg recently(banning of cards like emrakul and the copter). If we didn't have this mechanism I can tell you from my other lcg experiences - there would be maybe 3 top clans and it would change on around 2 year basis, and not by much. 
I think this is a very elegant solution as compared to straight up brute force nerfs.
And again you assume you are supposed to have the choice of role - you are not. They are not part of deckbuilding but balancing/keeping the game fresh - assuring that even though not all clans might be at the top at one time, there would be at least some changes from year to year how they play and where they place.

Exactly - We've chatted about this in different topics about how FFG could keep player interaction and control evident without having the story team or design team go crazy corrupting every faction in turn...  The suggestion I liked was the idea of creating different posts that would allow several clans to fill out - like Shogun, Left Chancellor, ect.  I think these role cards do exactly what I was wanting.  We can have these won and lost and traded over time - a constant reminder when you build your deck that "this is the role your clan has" and "this is the role you'll face with that clan."  The way they've designed it is just great - not only in the balance and availability of roles (I suspect most clans will get their "optimal" choice or at least a close second even without going to hate-drafting) but also in the fluidity of it.  The power of each role card could change with each card expansion, and the Role cards themselves can easily change and evolve each time they are reset - who knows if we'll use these exact same role cards for next Worlds really?
Giving the players the title of Hatamoto and Shogun is a great touch too.  I just hope those players are active in the online community, not just their local community.

Hey guys. I played at Worlds for AGOT last year.
There were 5 Tyrell players total and I placed was the top-placing Tyrell in 49th place. But that is somewhat misleading, I was 1 win from making top 16 with my Opponant match-win ratio.
Even the top of the "weakest" faction can still place pretty highly. I was 5-3 and played against some top decks. You don't get the top of faction by sheer luck.

To be honest, I think this is kind of what makes the choice of role card so cool.  Like, the game hasn't even released yet and we're all worked up over someone that may or may not choose the role we like, and which may or may not have a significant effect.  
The idea that player decisions within the game can cause this much of a reaction, and carry this much weight is part of what makes L5R so cool!  A game driven by player interaction - BOOM, here we go! 

And it worked out quite well!

The motion is seconded - The Yasuki family would be honored to aid in such talks!

Three thoughts.
First, the genius of this set up is its execution.  This role selection thing is not in the core rules, but simply in the Organized Play pdf.  So, if FFG sees that it had unintended consequences, they can just scrap it and move on.  No big deal.  In addition, this is only for Organized Play.  No one is forcing you to play this way casually, or even in your FLGS.  This is only in play for events supported by FFG kits.
Second, while it may seem like a big deal to get two provinces of the same element right now when there are only 17 total (have we even seen all 17?), more provinces will be printed.  While two void provinces may be optimal for a clan today, two earth may be better in six months.
Third, one of L5R's biggest draws is that the players have can affect the game on a level that is unseen in other games.  While the selection of roles is not earth-shattering, it is a dip into what draws many to L5R.  If you do not want some random player having an effect on your game/story, L5R may not be for you.  And that is okay!
I am cautious about this, but I am leaving my final verdict aside until I can get some games under my belt with this system.

Aren't the Worlds invitation only? Its not like it is going to be random people showing up for the Tourney, unless I read the article wrong - which I very much could have.  Also it is free to go to Worlds if you win a Grand Kotei.
"Top performers earn a personal invitation to the Winter Court—the World Championship—and Grand Kotei champions win travel and accommodations!"