Emulation is an extremely CPU intensive activity particularly when you are emulating a different instruction set at the hardware level. If you are emulating a gaming system rather than just running that gaming system, you’re doing it wrong (from a permacomputing PoV). The simple physics answer is to pick up an snes at a yard sale for $5 and save it from the landfill, instead of blowing a wad of cash on new hardware you don’t need. Then hack that snes to do whatever you need, such as to attach a copy console. I hacked a Wii to act as a media server, so it can not only play the old wii games but also play AVI movies from the LAN via samba.
Your take is like saying: I want to simulate a nuclear fission reaction in my livingroom… these old PCs suck and should be tossed. Of course if you select an obscure and heavy task you are limited in the hardware you can deploy for that.
Of course when talking about designs, that’s about the future. After a design has been implemented, it’s too late. You can change a past design but it would only be for a future production because a design has already served its purpose after implementation. Apart from that, you would need a time machine.
But the right to repair in the EU is not just about designs. Design is only a small part of it. If a dishwasher were to end production 1 year before the right to repair law is enacted, that last dishwasher is already under a statutory warranty for another year, and likely under a commercial warranty for a year or three more. So spare parts would already be in production just to satisfy warranty obligations. There would be nothing radical about extending that since it would not have stopped production anyway. It would be foolish not to take that opportunity. And with manuals… who loses manuals? Consumers do, but not likely producers. Mandating that literature be made available for old appliances would be reasonable, at least in electronic form. The EU would be foolish not to make literature disclosure retroactive. Some EU countries will even enact retroactive taxation. If they will do that, anything is possible.