My point is that a linked list is such a simple concept that anyone with real programming experience should be able to write a basic implementation.
It's a Shibboleth; I only care about your ability to perform the task because it tells me something else about you.
It almost levels the playing field in the sense that since no one actually writes these things, we're probably all equally half clumsy with them :)
Is this a good reason not to ask it in an interview?
I'd expect any competent software engineer to be able to implement a linked list without too much trouble. It's maybe not a great interview question (depending on your point of view, you may not consider it to contribute much positive or negative hiring signal), but I don't consider it a "gotcha" question the way a lot of people seem to.
I mean, I understand the linked list quite well, but in my multi decade software career, I've probably actually implemented one less than once a decade. So I think it's a very unrealistic interview question, and will sigh quite hard (internally) when asked to implement one in an interview.
You just can't please everyone...