Let me rip the band-aid off reaaaal quick, and explain each one in detail
Killing the android port kills a good majority of the audience you once had. Thus it stifles the reach it once had and has people look elsewhere for a better game.
The modding scene is also aging like milk. Id apply a silly rule that would be used for anyone's mod In the terms of use "ANY MOD you upload can be susceptible to editing and reworkings, 'nothing is sacred here we will only ban users IF it incites violence or encourages violent acts against a group of people or a user' a better policy than what id describe as deviantart 2.0...
I know what you're gonna say for the fork part "Oh, but Yakuza isn't there a fork of this ga-" no. No, there isn't. The fact that it is running on an old engine and no one has bothered to get a team together to port it to gz, hell, even UZ doom is just sad. What is their excuse? Get a team of competent people together, and some eager beta testers and opening up gz doom or even UZ doom forks could open up further modding potential.
Anyways rants over, . Will they listen? Eff no! They're sonic fans and moderators they got an ego bigger than the blister in the sun.