This was not the technology industry's first encounter with AI hype. The term was coined 40 years ago, and has been suggested as a description for almost a dozen periods in the field's history:

https://en.wikipedia.org/wiki/AI_winter

It's a term for when AI hype dries up, has happened multiple times since the 60s[0].

[0]: https://en.wikipedia.org/wiki/AI_winter