Often times, even professionals working with older, standard-definition video end up processing it incorrectly, or may be working with digitizations in which someone else already made an error. Interlacing is almost never handled by a "double framerate" method (in which a 30fps interlaced video, each frame consisting of two 60Hz fields, is transformed into a 60fps progressive video). As well, often times such video is even captured with every other field missing (more common in VHS captures than professionally-handled captures, but that's a slight digression).
Also, SD video really does look best on an SD CRT display. Often times, the upscaling to HD, as well as the differing visual properties of typical HD displays, will cause the inherent flaws of the SD material to be more pronounced. You won't ever get a true comparison without seeing the video playing on a decent SDTV. And honestly, playing these videos on an SDTV would probably look amazing compared to what you would have seen on MTV in the 80s and 90s.
If the rationale is 80s to 90s SD broadcast reference monitor quality parity on HDR/OLED displays for the masses, this is all I want.
As it goes for new digital transfers from 16mm or 35mm sources, it's a case by case thing to me, if the production looks "cheaper" when, it was not intended to by consumed beyond SD quality, better don't go over 720p remasters or it might look weird.
Often times, even professionals working with older, standard-definition video end up processing it incorrectly, or may be working with digitizations in which someone else already made an error. Interlacing is almost never handled by a "double framerate" method (in which a 30fps interlaced video, each frame consisting of two 60Hz fields, is transformed into a 60fps progressive video). As well, often times such video is even captured with every other field missing (more common in VHS captures than professionally-handled captures, but that's a slight digression).
Also, SD video really does look best on an SD CRT display. Often times, the upscaling to HD, as well as the differing visual properties of typical HD displays, will cause the inherent flaws of the SD material to be more pronounced. You won't ever get a true comparison without seeing the video playing on a decent SDTV. And honestly, playing these videos on an SDTV would probably look amazing compared to what you would have seen on MTV in the 80s and 90s.