Regardless of what is a subset of what, I certainly agree with the OP that OOP feels "anemic" in comparison to the dispatch-based paradigm of Julia.

I can't tell you how many times I've seen disparate packages written by different authors with no explicit effort towards interoperability "just work" together in Julia (e.g., [1]), something I have never seen to a comparable degree in any other language.

[1] https://www.youtube.com/watch?v=kc9HwsxE1OY