[yesenadam]

Well, there are 3 (FIDE) world champions in chess nowadays - classical, rapid and blitz. But the classical title seems magnitudes more important than the others. I doubt many people at all could name the rapid or blitz world champions in order. Maybe if rapid and blitz had the same candidates tournament and title matches that classical does, not just a single swiss tournament, they would be less random and more significant, maybe rivalling or overtaking the classical world championship one day. Not a bad idea.

[MiddleEndian]

Having different champions for different rules (even if they're just time-based) makes sense, kind of like how in pro wrestling you had the regular champion, the hardcore champion, tag champions, and so on, or in the case of boxing and MMA, weight classes.

However, the different boxing championship organizations are not really distinguished by ruleset, as the ring size, glove size, and even the judges are negotiated on a bout-by-bout basis, and certain title shots are for multiple titles. It's really sort of nonsense.