Well yeah reading Brainfuck is rather easy after all, it's just a few symbols. Understanding what the code does and what it's trying to do is something else, and there I think language matters a whole lot.

For example, const helps me a lot when trying to understand C++ code. If I see a const reference, I know this bit of code I have in front of me can't modify whatever it is referencing. My language at work doesn't have const references, so I'm never quite sure if a call does modification as a side effect or not. This is the kind of stuff that I think can matter when trying to fix something at 4am.

Now, Haskell as I understand it is rather pure, so side effects like that are not a big issue. But on the other hand it allows for embedded DSL's from what I understand, which perhaps could be an issue if my coworker were to get creative. Though as I said I have no background to judge Haskell on this, I just thought it was a valid thing to be concerned about.