Haskell is much more complex than C++, for one example. (How many language extensions does Haskell have now? A hundred?) C++ is easy to understand when you und

Haskell is much more complex than C++, for one example. (How many language extensions does Haskell have now? A hundred?) C++ is easy to understand when you understand the mental model its abstractions target. (In some sense you're right: the mental model of Haskell is mathematical, while the mental model of C++ is some sort of multi-core "Harvard architecture" machine. While it's true that math is a lot easier for the human brain to grasp, this isn't really related to language complexity per se.)