AI/ML barrier to entry is far simpler and vastly user friendly compared to crypto. Instant value return or gratification from ML products (GTPs and rest) is far more mainstream friendly.
Another view is the "loss" factor. Nobody, thus far, has has had their funds stolen or lost using ML products. I understand content creators and those who, unwillingly, contributed knowledge to learning systems did get circumvented but i'm talking about users/customers. Compare that to the negative stigma of crypto frauds and stereotypical association to illegal transactions.
Apples vs. rotten oranges in my opinion!
Most of "AI startups" are close to scams, i.e. they are oftentimes just interfaces to proprietary APIs that monetize on impressiveness of LLMs.
There is no moat. Anything even moderately profitable will be implemented in 4 hours by the whales.
This point of view is too simplistic, not everything needs to be a billion dollar idea or differentiated. You can make an absolute good living with no moat and good product senses. Even if you get outgunned, you move on to the next opportunity.