[ska]

Ok, we are bogged down in semantics, but I see where you are coming from. I don't buy the proper subset argument for reasons above (i.e. I don't buy the broading of AI to fit that idea of "intelligent agent", as it includes too many things that don't really fit, imo).

Unless something has changed radically since I stopped paying as much attention there is not actual agreement on these terminologies, at least broadly, in academic circles.

I certainly agree many current systems with a core ML component include other techniques from lots of areas including what you call "classic AI" as well as optimization, etc., but the ML is still the fundamental part of nearly everything recent I've seen. As pretty much every successful system of this type is a hybrid in the sense you mean, I don't find differentiating them from some putative "pure ML" approach very interesting.

There was some good work in very different approaches in the 70s through 80s, but that seems to have tapered off in the 90s really. I'm not very current though and would love to hear of newer interesting things in that vein.