I think this varies a lot from person to person. I find the effect to be incredibly subtle - one of my monitors reset it self to 60hz a while back, and I didn't catch the problem for days.

If something is not noticeable when it gets "better", but it leads people to notice other stuff is "worse" over time, then I'd argue it's not actually a good thing to get.

Imagine if someone said "this food won't really taste better to you when you first eat it, but after 6 months you'll find other food tastes worse". To me, this would not be a selling point.