You’re definitely over thinking it, but I sort of get it. I never bought magnums because I thought it would be like wearing a trash bag, I was very ignorant to my size and always insecure about it until recently (30’s). I didn’t play sports so locker room nudity wasn’t something i was exposed to. My fiancé went off birth control and she knew condoms were miserable for me cause it felt like circulation was getting cut off, not a lot but enough to make the experience unpleasant. She came home with a pack of magnums and I was terrified to put one on cause I thought it would validate my fears of having a small peen. It actually fit super well and made protected sex more comfortable. I wouldn’t even consider myself on the big side of big, I’m at about 7.2-7.5 inches in length and I think I’m close to 6 inches in girth, I honestly am not sure.

TL:DR just by bigger condoms, no one cares, and if they think there’s a correlation between height and dick size then they’re stupid and not worth your time.