The costume was originally designed to emulate the type worn by professional wrestlers of the time.
And circus performers. This is a good thing, how?
It's not a "good" thing but hardly a "bad" thing, either.
It's just that what Superman wears is not
underwear. It's part of a unitard/costume that's common for people to wear in a few different -granted rare- situations.
I think the biggest problem I might see with this costume it has that heavy rubber look to it that super-hero costumes have had for the better part of the last 20 years or so. Would it be that bad if the costume was made out of some-sort-of cloth or fabric? I don't think the heaviness and shininess works well or looks good at all on film. And Superman, obviously, doesn't need the padding and protection from weapons.
The Spider-man costume from that series of movies probably did things the "best" in terms of costume design but I really don't think a simple spandex wrestler's/gymnast suit that's been well designed would look that bad.
As noted above, the suit Reeves wore in the '79 movie was probably the best. I think it still has some flaws, I'm not a fan of the shades of the colors uses or the size of the shield but overall I think it looks fine.
Also, I'd prefer no \S/ on the cape, personally. But I can go either way on that one.