Season 1 especially
theres a lot of episodes you kinda had to be around for.

Season 2 & 3 hold up pretty well since they decided to put more emphasis on the characters. The characters deal with topical issues and they grow from it by the end. Season one did more spoofing of topical stuff so the whole thing hinges on you knowing the context, which has less replay value storytelling-wise.

you don't really need outside context for Gangstalicious or Huey Freeman Christmas, but episodes like the MLK ep are inside baseball.