As opposed to procedural languages, will it be valuable for me to study Haskell and functional programming paradigms?
If having an expanded skill set is valuable, then: yes.
One advantage you might pick up: parallel and concurrent programming. Procedural languages of the past tend to have no clear notion of side effects, as a result writing parallel programs in them is difficult to do correctly. Functional languages (in particular, ones that limit side effects like Haskell) have a lot more to say about productive parallel programming.
Having that skill up your sleeve can't hurt.
