Saying "non-argument" and ending it there is not useful, but in this case it's shorthand for something along the lines of "not even wrong", and I think that's a valid answer for some (not all!) of the points in the OP.
To pick one example: the author gives an example of an eta-reduced function and then says:
let fn1 a b c d = ... do something ...
let fn2 a b c = fn1 a b c
fn2 a b c d
> and you're like ...wtf... where the hell does d come from.(Or their criticism of partially-applied functions, which is essentially the same thing.)
This is a "non-argument": the only thing that is being made clear here is that the author hasn't spent sufficient time learning the idioms of an unfamiliar style of programming. Yes, horrible partial-application like
f = (g .) . ($) . (. (. h))
or whatever is always a bad idea, but saying that writing map f
is always worse than map (\x -> f x)
is much more likely to be a symptom of unfamiliarity than a deep, cutting critique of functional programming style.