My personal rule is that I'll buy it as long as the original creators are profiting from new sales. So I'm happy to buy Switch games, but I'm probably not going to buy N64 games because they're not available from the original devs.

I may buy even if that's not the case if buying is a better experience than getting it some other way.

If DRM-free digital copies existed for movies, I'd buy them. But they don't, so I buy physical media and rip it to my NAS.