the hot boys helped define an era. those other 3 groups didn't. do I really have to touch on their cultural influence? like really homie?
they were packing arenas - with hood crowds. I remember in 2000, they headlined & co-headlined 2 major tours. packing some venues 3 different times within the same year. those 3 groups that youre mentioning, never came close to doing any of that.

you gonna ignore "get it how u live"? that's better than most of the albums you listed as well.
having a 3-4 year run, hitting the apex of the game, then breaking up >>>> decades of dwindling around the midcard or just flat-out getting lost in the shuffle
and outkast aint make no great music for no decades. they have an arguably classic debut, a hot follow-up, another good album, then they crapped out in quality but went pop and made crazy $$$.