That may be the case but other genres, such as shooters (first and third person), have found ways to get around it. Fortnite, for example, has nowhere near this issue whereas Quake 3 is plagued by it. The 100-player battle royale structure of Fortnite is one mechanism I think helps to mitigate the problem of overwhelming skill gap.

This kind of thing hasn't really been tested in RTS games, which usually focus on 1v1s.