Every once in awhile I do watch an pre-HD era TV show on an older CRT. Not just for nostalgia, but that some shows seem to look much better on them than unconverted in HDTV (at least to my eyes).
Ah, the rose-colored glasses effect that also makes "tube amps sound better."
As Makeshift said, it's more than simple nostalgia. Older shows weren't made to be seen in such crisp, clear resolution. The flaws are more noticeable.
Have you ever seen pictures of some of the props and starship models? Up close to the real human eye these props can look cheap and fake and sometimes even sloppy, yet they look good on screen.
Sometimes these things weren't made to be viewed at the highest resolution.