Most of this is a discussion about semantics, which is silly.

In 99% of industry, AI is used as a synonym for Machine Learning. The remaining 1% refers to Artificial General Intelligence, which is a long term vision for what might be achieved using, again, Machine Learning.

I think a lot of it is ANN based now, but it worked pretty well when it was just KNN. Calling KNN "AI" is pretty cope; it's just a database query. Of course, the large ANN networks are also more or less just a database query refactored as a function transformer, but nobody likes to talk about that.

If you don't consider machine learning AI, then there are no existing instances of AI. It's all either ML or vaporware.

The state of the art is using transformers I believe, which are a special kind of ANN