Nah, blockchain has extremely limited applications.
Generative AI legitimately does have quite a number of areas that it can be made use of. That doesn’t mean that it can’t be oversold for a given application or technical challenges be disregarded, but it’s not super-niche.
If you wanted to compare it to something that had a lot of buzz at one point, I’d use XML instead. XML does get used in a lot of areas, and it’s definitely not niche, but I remember when it was being heavily used in marketing as a sort of magic bullet for application data interchange some years back, and it’s not that.