I think the GP's point was that functional languages give you similar benefits, but with more uniform and disciplined behavior of many language features. Why FP is not more widely used compared to imperative language is another topic though.
I love JS because it's flexible and doesn't lock me into a paradigm. I can be as strict as I want to be. In the end, I think it depends on how someone thinks about problems. I tend to bend my thinking depending on the type of problem and how I might optimally solve said problem. When I need something else (often for performance), I'll circle around at that point for that part.