From my experience if you are not dogmatic/extremist about it you can gain a lot, so I try to do things in a functional way in my non functional languages.
Yeah I totally agree. I think writing code which is "functional where possible" is super powerful and offers a ton of advantages. Trying to cover that last 20% of cases where you have to bend over backwards to create a performant functional solution, to solve a problem which is trivial with a little bit of mutability, doesn't make sense.
