Disks are for games I want to be able to pull out of a box 10 years from now and go "oh man I remember this". I have the box from a DSi that I filled with GBA games, and a shelf for Switch and PS4 games that, when they're retired for something else, it'd be nice to come back to once in a while. My daughter has gotten into my GBA games lately, so that's been nice.
PC games, they're so much more available. Steam is steady, GOG is steady, I feel I can leave it to them to keep and I'll have any particularly treasured games 10 years from now, anyway.