I don't know that I'd say the PROBLEM is the ability for certain corp cards to tag the runner without precondition; but it combines horribly with the direct-damage options that need tags.
In the original NetRunner, there were few ways for to tag the runner during the Corp's turn. All of them relied on the Runner doing something the previous turn - make a run, usually - that depended on the card in question. Even these almost universally functioned by allowing a Trace instead of simply handing out tags. The only one that would directly tag the Runner was Trojan Horse, which required them to be tagged.
These were offset by some pretty robust options for the Runner to avoid tags - Nasuko Cycle, Fall Guy, Leland, Nomads, the Weeflerunner, etc, and most of those had an extra beneficial effect to go along with them. These existed solely because cards like I Got A Rock and original Urban Renewal made tags so nasty.
What we're seeing now is an increase in the ability of the corp to dish out tags with no action on the part of the runner, combined with a card pool that restricts the options to avoid tags in the first place and then further restricts those options because of the new faction system. Even if you consider the availability of those few counters sufficient, it means the game comes down to whether or not the Runner can get them and get them installed before the Corp comes across a mere two-card combo and flatlines them.
It doesn't have to be two Scorched Earth. It only takes one, unless the runner keeps their hand above 3 at all times. That's a huge burden. As has been pointed out, if they're playing right the Corp may have to stage it over an extra turn and have two more bits, but it's easy enough to trash Crash Space once they're tagged before you drop the Urban Renewal.
If we consider the original balanced (which I do - tag-n-bag was viable but hardly dominant as a corp style) the new system improves the corp's ability to tag, seriously degrades the runner's ability to avoid tags, makes those few abilities faction-dependent, and keeps the lethality of the "If runner is tagged" operations the same. That's a bad combination.