I wouldn’t say there is “no” use case.

For example, a friend of mine is landscape gardener and he regularly uses AI to basically help customers understand what he plans and how it would look. I made him a small webapp where he can simply snap a pic and writes a prompt like: “To this garden, add a small, round base filled with pebbles in the middle, add a bench and two metal poles left and right”. AI generates the pic, he rewrites the prompt a few times and once he’s satisfied, can show it to the customer who then exactly knows how it looks. He used to do that with photoshop himself which took him a lot longer and customers were more often unhappy with the outcome because the picture didn’t show it as clearly as the AI generated pictures do, so he had to do some adjustments, which obviously eats into the profits.

So yeah, there is actually a good amount of use cases. However, none of those use cases requires literal trillions being pumped into the AI industry.