Yeah, the hype has died a little now, but over the past decade or so there was definitely a surge. Functional paradigms are definitely useful, but like a lot of things you can take it too far. I think one of my favorite criticisms was that the real world is mutable and has state so most programming languages will have to have that everywhere.

You can get a lot of the good from functional programming in non functional languages just by using immutable data types and pure functions.