That is very subjective. For example, Lisp has a very simple grammar, yet many people find the minimalism complicated in how it manifests in paren heavy code. Likewise, Haskell's reliance on abstract mathematics is definitely going to turn many people off to it. "It's just math" is often taken as a negative, not a positive (depending on the person).
Natural language is built around all sorts of non mathematical ad hoc concepts, yet we seem to use it just fine. Of course, it might not be the best way to talk to the computer, but it is definitely "accessible."
Most people don't know their natural language as well as they'd need to know it to accurately and unambiguously describe things. The only reason natural languages are even useable is because the human interpreting them has a huge amount of context to infer the meaning from and do error correction with.
The reason programming languages exist is to simplify the language used to describe things so they can be interpreted without too much additional context and unambiguously.
You aren't wrong. But there is a good reason objects remain popular even if they aren't ideal by any means. With objects, you get to rely on your built in metaphor capabilities of natural language, your ability to think ad hoc. Now, that gets you into trouble quickly because the computer isn't human, but it shouldn't be a big mystery why OO remains popular. Haskell makes imprecise ad hoc thinking hard to encode, because well..eat your vegetables, they are good for you!
There's no abstract mathematics in the casual Haskell user's experience. I have no education, no background in math, self-educated or otherwise and use it effectively and happily for industrial purposes.
Programming in Haskell is as close to math as one can get in a general purpose programming language (theorem provers are more so, but not general purpose). You might just have a knack for it even without formal training.
Natural language is built around all sorts of non mathematical ad hoc concepts, yet we seem to use it just fine. Of course, it might not be the best way to talk to the computer, but it is definitely "accessible."