McGregor = Metallica
Was once regarded as top tier, had a lot of ups and downs (mostly downs) and still regarded as an industry pioneer. Draws ungodly amounts of money and gets marketing.
Khabib = Tupac
GOAT tier, left too early.
Anderson Silva = Jimi Hendrix
Pure fucking magic during his peak. Fans were heartbroken at how his career ended.
GSP = Tool
Started out with a cult following, blew up into the mainstream, consistent with his output. Fans think they're better and more sophisticated than everyone else.
Mike Perry = Insane Clown Posse
He sucks, but has a cult following.
Frankie Edgar = Josh Homme.
Enjoyed a clear peak, but remained relevant throughout many eras and knew how to change with the times.
Khamzat Chimaev = Kurt Cobain. (to be confirmed)
Major disruptor. Just like Nirvana killed hair metal, Khamzat will kill the WW and MW divisions and will go down as a legend. He almost left too early, as we may have lost him to covid.