Removing RAM chips off old cards is uneconomical, until it isn't. With things going the way they are, if you've got a card with soldered on RAM that could be transplanted to a newer card, I think you'll start seeing that happening.
Chinese recyclers already do this with laptops
It has already become economic. While not exactly the same, the NVIDIA 2080 11GB cards are notorious for being upcycled with extra RAM: https://www.reddit.com/r/nvidia/comments/146us12/nvidia_gefo...