Yeah, I feel the same way. Felt like they nailed it with the Boost gameplay, polished it up to really handle well and abide by some of the same standards that I feel some of the classics do (Flow being important as all get-out), then they just went "OOPS" and threw it aside. It feels like they should really get a solid base for whatever it is they want to do, polish it up as best they can, and expand upon it accordingly, instead of trying to throw it under a new bus every time.
It almost feels like there are two forces within SEGA/Sonic Team, There's people in there that are super talented and have a clear vision for what they feel Sonic should be and are genuinely inspired people, the team that started in with Unleashed, and then there are the less... caring folk, that just focus on all the wrong things, misread fans, and undo the work of the people that are working so hard to get Sonic back on track (For how many years now?)
Example, wasn't the Unleashed Sonic design chosen to unify the Sonic brand? Isn't that the excuse they used for why Modern Sonic was in Sonic 4? Then who had the great idea of "You know what Sonic needs? WESTERNIZING! Let's throw him at some American dev team and hope everything goes well!", Now we have "Games Sonic", "Boom Sonic", and possibly an unrelated "Movie Sonic", those universes won't likely interconnect, some (younger?) fans will be confused as to why Knuckles isn't ripped in "Sonic the Last Wispbender", but he was in "Sonic Boom 2: They're Chaos Emeralds This Time!", and in "Sonic the Hedgehog: The Movie (2015)" (not to be confused with the English title for the OVA), Knuckles was a sloth, and was pinkish.
It's infuriating to think about how possibly simple a great Sonic game concept could be to come up with, and how far off Sonic Team (and others) have been for so long.