I think that’s true as far as it goes, but there are further reasons why Haskell is more difficult. Here is one:
In Haskell, the lack of parentheses for function calls plus currying means that to read a function call, you need to already know how many arguments the function takes, which I feel adds a new level of difficulty over languages where you can often guess what a function does based on its name, without looking it up.
As a result, often Haskell reads more like math, where without knowing each symbol’s definition, you’re lost.
I’ve seen cryptic JavaScript too, but less often.