Mostly just on Town Missions because of the loading -> one line of dialogue -> loading, other than that, the loading screens are similar to playing a PS1 game, imo. You get used to it but it REALLY becomes a HUGE pain when you fail a town mission and have to re-do it. And then you fail again.
2006 kinda only has Elise and Silver, and giving Blaze a dynamic with Silver - Blaze has way way more character-defining stuff in Sonic Rush than 2006. It's really a game for if you're a Huge fan of Elise, Silver or Mephiles.
Adventure 1 establishes all the characters, it has Tails learning to be self-reliant, Knuckles figuring out his past, Gamma. Adventure 2 has Sonic's rivalry with Shadow, him telling Tails and Amy his last words, Knuckles getting a rival-gf who's a fun character on her own, alllll the Shadow stuff
plus, yknow, it's not like Adventure 1 and 2 doesn't have their fair shares of misguided and janky things to them, but 2006 lacks the components that these games have that really elevate them. It doesn't have a Live and Learn, or huge pivotal moments with characters people love
THAT BEING SAID, I've only played Sonic's story so far, and it could be that I'll be running into MUCH bigger issues with Shadow and Silver. There's quite a lot about 2006 that's janky and misguided, but it's much closer to something everyone would be comfortable to call "Adventure 3" than I thought
There have been several levels that I hadn't really died or ran into any issues with, because I've played Sonic games a lot before. But if I didn't instinctively know what the level wanted out of me in split-second decisions, it's possible I would've eaten dirt & ran into huge jank while I was at it
Once you understand that, you also understand why there are so many Sonic fans who "defend 2006", who say it would've been "a great game" if it was properly polished. I looked down on people who said that, but now having played it, I completely understand where fans like that are coming from
-> which it is a pretty unique kind of game that doesn't quite exist outside of Sonic, so it could be that part of its huge Bad Game legacy comes from people who are still figuring out "how to play a Sonic game" exponentially compounded with fighting the jank of 2006
All the ways in which it is clearly unfinished are amusing and obvious, without feeling like torture. For someone who hasn't ever played a Sonic game, esp in 3D, it could be that it's way more frustrating, as they're still figuring out a lot of the language and inherent troubles with the "genre" ->