Wearing them to a game, when actually doing sport or when at home is obviously fine.
The rest of the time, not so much. Not that it's some terrible thing but it's just hard to actually look good in them, I think. Partly because a lot of people noticeably don't look like athletes when wearing them, partly because they can lend themselves to a chavvy look depending on what else you're wearing, partly because they're so associated with youth culture that it can read as quite an immature clothing choice as you get older but mostly because they just generally aren't particularly stylish looking. Though even if you're wearing the most stylish looking retro shirt around with the rest of your clothes all on point to make the best of it, you'd still need to be fairly young and fairly good looking to carry it off as a look, I think.
But then some people like going around in mullets, slogan t-shirts, bootcut jeans and square-toed shoes too. If that's your vibe then that's your vibe. And tbf a lot of guys probably think of them as being different to "normal" clothes when it comes to whether they actually look good or not.