There are lot of grievances to take with Sonic games, I don't really feel like "not long enough" is on the upper echelon of priority. That said, I've heard a lot of praise for the controls and I'm eager to hear what real humans have to say about how the autistic hedgehog feels to play. I don't trust Sonic fans or game journalists.
From everything I've seen, this is just boosty Sonic applied to a big BotW landscape. While the idea of blasting around a big open world sounds like a fun diversion, the way Sonic looks to interact with his world isn't anything to write home about. I think when people dream of an open world Sonic game, they want a game where you don't just hold X to run really fast across bumpy hills. They want to do flips and run up walls and launch into the air off of (natural) ramps and do all the crazy shit that Sonic does in the CD opening and in the OVA. This is part of the reason Sonic Utopia briefly exploded when it was first released. Even normies who didn't give a fuck about Sonic were impressed with how cool it was to do all of that crazy Sonic shit and be rewarded for playing well.
The way Sonic just sticks to and runs up walls like somebody hit 2x speed on BotW Link climbing, and how there are still so goddamn many speed boosters and springs and rails makes it feel like they missed the point. It all looks so stiff. I really can't see anything but "Sonic Forces but with a big open hub world" when I look at this game. The baffling focus on combat isn't really helping in that regard.
I dunno. I'm trying to put my bias against Sonic aside here and really look at this game for what it is, but I think more than anything it's being hurt by my expectations for an open world Sonic than anything else. I'm way into games that are super fun to control, where just the act of moving is a thrill, so this just all seems like a huge missed opportunity.