Lies of P is available on other consoles besides Switch 2. Of all the consoles on which it's available, Switch 2 offers the worst experience.
Dark Souls: Prepare to Die Edition runs at 30 fps on consoles. PC CD keys used to be available on G2A and GOG. If you can find one, installing the DSFix mod lets you play at 60 fps and puts the graphical quality on par with the remaster. The remaster is just PTDE with DSFix and a few other quality of life mods baked in.
PTDE with DSFix is my preferred way to play DS1, but way more people play the remaster and there's no crossplay, so multiplayer basically doesn't exist on it (although some people may argue this is a benefit).
I bought the Demon's Souls remaster on PS5. It was good, but I think I slightly prefer the original. To me, the janky look is part of the atmosphere and the appeal. But, again, the OG Demon's Souls servers are offline so no multiplayer is possible on that version, but DS multiplayer is.... well, if you know, you know.