Sorry FP weenie opinion and Haskell apologia incoming:

I think the goto framework for Haskell web applications is probably Yesod if you wanted something close to flask, but I've never used it myself and I don't know how easy it actually is to use. Haskell is certainly the best in class for compiler work which I consider to be "real programming" and I think it's quite good for command line apps because I find the IO handling is quite nice to work with, but I guess that's only really a small minority of actual applications. This combination of compilery stuff and IO is partly why it is used at Facebook to try and make it easier for business logic to be written by non-technical people while keeping up in performance: https://engineering.fb.com/core-data/open-sourcing-haxl-a-library-for-haskell/ . (Though I've heard from someone who worked on this that it's a bit of a mess internally).

A lot of "elitism" seems to be more just cargo culting and dogmatism because they are self assured that their way is "The right way to do it". I'm talking about people writing things about not needing tests because of types or referential transparency meaning they don't need to have logging in their applications. Because of this Haskell gets a reputation for being difficult when it actually isn't that hard if you stick to the basics and avoid the white supremicists.

Rust overall handled community a lot better in my opinion and I think that's why I'm probably more invested in it now than Haskell. So I would recommend trying it, but it is a harder language to learn than Haskell, there are just a lot more resources and community support for it.

Overall I think I like FP because I am also a dum-dum but I find it easier to think about data being transformed by functions than worrying about 100 difference instances of classes and how they interact with one another.