LogFAQs > #894391269

instead of making a 3d sonic game, they made a fucking tech demo starring sonic and friends
they mistakenly thought that people played it for the shitty side modes and not for the actual sonic-like parts, so they kept doing that shit in every game since
they don't make a genuine effort to put the series into 3d, they just make hackjob platformers with strange mechanics and with sonic characters in them, regardless of the bad tonal or gameplay dissonance that tends to result in unfavorable or bad games
they don't even fucking try with level design, opting to make insanely long marathon levels that repeat over and over and never have any meaningful player interaction, fun mechanics that utilize and give access to speed, or even good use of three-dimensional space since everything is a goddamn fucking corridor (with sa1, the first attempt at putting the series in 3d, the only game that even tries at all to have memorable setpiece and layout variety)