I know this is a troll comment, but the situations you see these variables are in highly-polymorphic( generic ) code in which there are no more descriptive names.
It’s like the use of `T` as a name in most Java or C++ generics.
I don't see it as a troll comment
This stuff is utterly incomprehensible to me as well, but I don't think Haskell is trying to be a mainstream use-it-for-everything language. It does get plenty of real-world usage and the people who like it really like it, so for a language so complicated to get as much use as it does sounds like it "took off" perfectly fine