Actually the tech was probably about the same. Bear in mind the technology hadn't really changed in 4000 years. When you have a huge galactic republic/empire you would never get massive leaps in technology, because a lot of the species are already advanced enough to have discovered every technology of use. For any given race there is always an older more advanced race.
The ships from the clone wars era are only outdated because they are no longer in production and parts are scarce. Much like cars from the 80's and before. Look after them well and they would still be servicable.
And frankly the Naboo star fighter wouldn't be much different than an A-wing. Highly mobile, lightly armed, but also limited production based on Naboo for the Naboo PDF. Also lacking a hyperdrive not all that useful.
Honestly I'd wouldn't mind seeing Jedi starfighters and Jedi interceptors, but I don't think it is likely. I am in favour of a neutral faction though.
The tech may have been the same, but there may have been cases where just more refined versions using the same tech came about. Also there were new developments just not always groundbreaking.
There might be some clone war era or even pre clone war era starships that were equal to or superior to the Xwing. I think the Jedi Starfighter and ARC-170 may fall into those categories. We also can concoct a good reason for them not being found in the Rebellion era--Jedi Starfighters were probably expensive with very limited production, and ARC-170s may have had their shipyards retooled to maker other ships (maybe capitol or maybe TIEs) once clone troopers were abandoned.
The fluff is pretty clear that 'in it's day' the Z95 headhunter was a good and highly regarded ship, but the Xwing is better.
If a bunch of other old ships were equal to or better than the Xwing, then those companies would have kept on making and selling them. If a bunch of other older ships were equal or better than the Z95, then the Z95 wouldn't have been held in high regard.
Making many ships of the Z95 era equal to or superior to the X wing is counter to cannon.
Also, for many of the unaligned fighters from Xwing Alliance video game, the fluff states they were on par with Z95s