I’m arguably a real man’s man with typical man likes and man opinions but I won’t for the life of my understand this macho stigma against pissing sitting down.

You have no toilet paper at urinals so you put your member back into your underwear with more residual piss on it than you would’ve otherwise, and splashback of piss particulates back onto your pants is also a thing. Especially when you piss in or at somethings that’s not those round specifically purpose built porcelain urinals.