Dan at Extra Credits has been playing Sonic Generations for animation footage. In his third video, he asked commenters to describe what they liked about modern Sonic games. He himself is one of the many who finds them lacking.

In a meta sense, being a Sonic fan is rather like being a Star Wars fan.

When a new installment of your beloved franchise is announced, there's a tense wondering anticipation--will this be one of the good ones, or one of the bad ones? Then, the ultimate truth of it is that you win either way. If it's good, you get a good game; if it's bad, you get material to make fun of, which might turn out to be surprisingly good for speedrunning.

Like Star Wars, Sonic is a franchise that requires a bit of curating. If you've never played a Sonic game, you'd do well to consult someone who is to find out which ones are worth your time. (S3&K or Sonic CD in 2D, Sonic Colors in 3D.) Those who know have the fun of being experts, of knowing the details of an extraneously large cast of characters across multiple continuities...and perhaps the smug elitism of designating their favorite subset as "the only good one".

On some level, one might simply accept that the different eras of the franchise are essentially different experiences: not even intended to feel similar to each other. One can say with equal validity that the change was not for the better. Most people will feel favorably about whichever was the first installment they liked, even if others prove to be better on close inspection, and all later installments feed off the resulting nostalgia.

And no matter what else happens, you can be assured that the soundtrack album will always be amazing.