You're right that in the strictest legal sense I am breaking the law if I download a ROM or ISO, but most of what I play can't be obtained at all as a purchase, so I don't have a problem with it morally. I've bought stuff on gog when it's appeared after I played abandonware versions for instance, so I'm doing what I can to be moral even if not legal. Regarding those emulators, I'm not sure what you think a court case can do in terms of stopping me using those emulators. The genie is very much out of the bottle. If a court forced microsoft to block every emulator from running in windows, no problem I'll just run it in linux and don't forget I can run what I like on linux, compile bits from source if I wish, etc. I'm pretty confident that nobody is going to take away my emulators.
Re already-downloaded games, most game stores require phoning home to the store for those games to function. I'm not sure of the Switch situation but I'd be surprised if that wasn't the case, given the need to verify ownership and not just let people pass files around willy-nilly. As for Steam - if steam dies I need to have locally-downloaded copies and I need to get cracks for those games. Those won't disappear any time soon, and indeed if Steam died I'd expect a lot more interest in such matters. Don't forget, the PC is an open platform unlike consoles, so users always have many ways to skin a cat. A locked-down console can have games removed remotely (as we've seen with PT), its authentication servers can be turned off, etc.
Indeed agree to disagree but fwiw I always enjoy a good debate, nothing wrong with disagreeing so long as everyone does it with reasonable respect and with proper explanation of their viewpoint.