The obvious difference is that AI has abundant use-cases, while Crypto only has tenuous ones.
Maybe there is added negativity considering it is a technology where there is clearly a potential threat to jobs on a personal level (e.g. lift operators were very negative towards automatic lifts).
What happened with previous AI hypes, the term AI was abandoned and the techniques and disciplines were "rebranded".
Probably will happen again. When something works and we start to understand how and when it works (and especially when it doesn't) it stops being "AI" and becomes something more boring.