Given that's what folks have been asking, over and over and over again, I should think the answer is obviously "yes".
It may not be relevant
to you. But at the very least
@pemerton has repeatedly asked questions along these lines and gotten pretty much
nothing in response (other than, as stated, merely reiterating the non-answer of "I picked soup A instead of soup B because soup A is soup.")
Uh...what?
We're literally talking about whether you know how difficult a climb is. How could that possibly NOT affect play? It's literally right there (on the soup label?

),
specifically about whether and how players can make decisions.
Whether there are "fixed, hard, universally applicable rules" is irrelevant.
There must be
some kind of decision procedure, because you have insisted that the GM is not being arbitrary, they aren't just doing whatever they feel like. "Realism" was given as the decision-procedure, but regardless of whether that is a useful standard (I still don't think it is, but I am leaving that aside), if realism is the decision-procedure, it cannot help the GM distinguish between doing the work to make option A realistic vs doing the work to make option B realistic. Hence, there must be
something more to this decision procedure. It doesn't need to be "fixed, hard, universally applicable" anything. It just needs...something else beyond "realism", as
almost anything can be made "realistic" by GM effort, doubly so when vast swathes of the world remain forever behind the black box.