Sitcom means situation comedy. If it’s a mostly comedic show, then it’s a sitcom. Abbott elementary is definitely a sitcom
More of a mockumentary to me, like the office
But I get what you mean. That's why put them in the kinda category. I guess it can be considered both, but I usually think of shows like family matters or fresh prince when I think sitcom
Filled in front of a live audience (or feature a laugh track), Ensemble cast, made for syndication, primarily comedy but also has serious moments meant to teach a lesson or raise awareness about current events, and usually recycles the same sets
Things can be mixed up to keep it fresh. Some elements might also be present that I forgot to mention, but that's just how I think about it