Calling Lean "AI" is quite a stretch. Though I'm also in the camp that dislikes the inflationary use of "AI" for LLMs, so I have sympathies for your viewpoint.

Finding a path in a maze was AI once.

I think that definition is pretty obsolete for the last 20 years.

To me "AI" is machine learning, statistical algorithms trained on data. That's not true for Lean.

So basically anything we don’t know how to write an algorithm for? I see where you’re coming from - but at the same time it’s actually an AI meme and smells of permanently moving goalposts.