Yeah I read up on this a bit as I was very impressed by the quality. It was shot on widescreen film so they could just rescan (if that’s the term?) the film at widescreen HD resolution. I think they had to retouch or adjust the crop in some scenes because there was stuff off to the side which you weren’t meant to see, which was out of the 4:3 area but inside the 16:9 area.
Some of the special FX shots look bad because they were digital and so they’ve just had to upscale them, but overall I was really impressed too. It’s nice because it lets you enjoy it all over again without being distracted by how “bad” it looks on modern TVs
Space above and beyond in comparison looks pretty terrible from what I have seen. It’s not even wide screen.
I think X files was shot on film perhaps?
I’m not sure if what we have now on say Disney plus for example is a remastered version but certainly it holds up very well.