Imho the problem is the fixation on parser generators and BNF. It's just a lot easier to write a recursive descent parser than to figure out the correct BNF for anything other than a toy language with horrible syntax.

I would argue the opposite: Being describable in BNF is exactly the hallmark of sensible syntax in a language, and of a language easily amenable to recursive descent parsing. Wirth routinely published (E)BNF for the languages he designed.

The problem with recursive descent parsers is that they don't restrict you into using simple grammars.

But then, pushing regular languages theory into the curriculum, just to rush over it so you can use them for parsing is way worse.