I do. The name foldr_k_z doesn't say what the function is doing. It's just syntactic punning on a function call with two additional arguments. That's actually negative for comprehensibility. Names should be semantic, not syntactic. And that name doesn't say a thing about its meaning. The most it tells you is that it's related to foldr and its k and z parameters. But the details? Well you have to look for those. When you look at the definition, you discover that the it's the foldr worker that closes over k and z. You could name it foldrWorkerThatClosesOverKandZ, I suppose. But does that name contain any information that isn't present in the context? Does it help you actually understand anything?

I'd argue "of course not". You already know that it's the foldr worker because it's a local recursive definition inside foldr. And you already know it closes over k and z because it uses them without defining them locally. Nothing in that name provides additional semantic value.

You could still use it anyway, on the argument that a little redundancy can help aid reading. But the more Haskell code you read and write, the less that redundancy helps you with anything. On the other hand, the proliferation of names that contain almost no semantic content starts to drag on you. And so an idiom was developed for naming recursive workers that do the core job of what the parent's name promises: just name it "go". Nothing to think about. It's reduced down to a level that communicates exactly that it's not clever. It's just doing the thing it has to do. And it's standardized. If you see it, you know exactly what it's doing. There's no need to waste time mapping a new name into your existing set of well-known patterns.

So... As to the original argument's point? I think it probably is awkward for pedagogy. But it's absolutely better for actively using the language.