It's good to see, yeah. Well, there's a lot less penises and swastikas in that video ,but maybe that's youtube limitations. Mario and Sonic are both known for getting a crapload of ROMhacks to this day, and I guess Pokemon too although Pokemon tends to be more involved.
Just strong communities in general.

They might still be around because they're harder to get DMCA'd into oblivion (especially sonic ones), whereas if you make some shitpost YTP for example it'll get DMCA'd and removed from youtube.