Except some of us understand these concepts, see how they can be used, but yet don't understand why we would ever use them.
In all these sort of articles I've never seen something that can't be done simpler with a bit of mutability sprinkled here and there. Sure having something 100% pure is great, but I don't know if I want that if it requires a 10x increase in complexity.
mutability increases complexity by 10x. Higher kinded types do not, they're unfamiliar and a bit weird at fist, but end up simplifying things.
Abstractions make code easer to reason about (Go read about parametricity! really!).
Mutability doesn't even help you from a superficial level for some things. Sure, if you're shoehorning a state monad somewhere, a locally scoped variable might look easier. However, try to fix 'Futures' without monads? It's much much less elegant.
Presumably you are no longer in the audience for these blog posts. My impression is the number of people like yourself who understand the concepts completely and decide not to use them is vastly outweighed by the number of people who don't understand the concepts, or think they do because they've read a blog post, but because they have no practical experience actually don't.
In all these sort of articles I've never seen something that can't be done simpler with a bit of mutability sprinkled here and there. Sure having something 100% pure is great, but I don't know if I want that if it requires a 10x increase in complexity.