Some of us have feet issues and NT is a great resource for getting specific info. For example I’m a tts 10.5 (measured on a brannock), but my left foot’s pinky toe sticks out so if the shoe runs slightly snug, I get extreme pain after a few hours wear (if not sooner). The lost and found Jordan 1s? Literally unwearable to me in a 10.5 due to pain. And I wore them 7 full days to break them in. Different insole didn’t work either. Had to sell them and buy 11 and they are perfect and I can wear them all day with no issues. And that’s just a half size difference for me. And everyone has different feet and their own sizing issues. You’re lucky that one size always fits you. Not everyone is that lucky.
Also no one in here is going up or down 2-3 sizes lol. That’s wild. A half size up or down, sure. But no one is wearing a 9, 10, 11 in different Jordan 11s.