Founders and Product Managers: Please Answer this. Why is Fireman NOT Called Waterman?

Isn’t it obvious that a fireman be called waterman? After all, they bring ‘water’ (and not fire).
The thing is that firemen are identified by what they solve and not by what they do (or what they bring to the table).
If yes, then why do you identify your startup/product as ‘AI’ / ‘ML’ product?
Why do you still think about your own product and not the problem you are attempting to solve? Why do you want to be identified with your ‘tech stack’ and not ‘customer stack’?
If your answer is : hey! this is what investors want to hear (and this is more gimmickry) – well, we all internalize what we speak.
So please repeat with me: If a fireman is not called waterman, I won’t call my startup an ‘AI or ML’ startup. I would give it a ‘business’ identity driven by what the product solves.
[Excerpts from Product Management Course.]