What's wrong with a diverse fanbase? Every successful long running franchise eventually diversifies and has a variety of fans. Look at TMNT, Star Wars, DC and Marvel universes. The key is to have quality in the different branches.
There's nothing wrong with diversity in any fandom.
But with Sonic's its a different story.
It's gotten out of control, too one sided and too elitist. You can't go anywhere without being harassed by the worst of the fandom,who consistently complain about the mediocre Sonic releases, whine about mobile hits like Runners and Dash, insult and berate people and other Sega fans who disagree with them, while again, nitpicking EVERY little detail about Sonic going as far as asinine,trivial things like his pupil color and character design.
The Sonic fandom in general has become a pariah. They are hated by the gaming public and often scorned and mocked. SEGA is taking the right steps in alienating these people. People like Richard Kuta represent the most dangerous and extreme elements of the fandom. He frequently harassed SOA to the point where it became criminal about a Sonic movie being made.
To put it lightly, Sonic's fandom has been invaded by too many freaks. Who I believe are too extreme,nihilistic, and one dimensional.
Back when I was in HS, the Sonic fandom was nothing like that. It was civil, it was open minded, it had positive identity, it had hope, good vibes.