I still haven't played TLoU2, and I've managed to avoid all the spoilers (so please don't spoil anything for me)... I've been waiting for a PS5 remastered version, but it doesn't feel like it's coming now. So I've no idea what's coming, but I'm looking forward to it.
I think if Last of Us Part 1 sales are good on PC then they will release Part 2 on PC.
At this point they will need to boost the textures and graphics, so a PS5 remaster will also happen.