Exactly. All about the new model.
I’ve said this many times on NT: The XI was the first shoe I ever saw move so quickly at retail. Up until then, you could count on being able to eventually find every year’s J on sale at places and/or at outlets. They were attainable in-store for months once they released. I knew plenty of kids who got the old model way late in the game or once the new model came along, always on deep discount.
Personally I can’t say how EVERY colorway of XIIs sold. I got my Taxis on day one after seeing what happened the previous year with XIs. That’s all I cared about so once I had them, I was good. I don’t recall seeing white/reds on shelves for long, though. I do seem to remember the playoffs being available for a minute because I pondered buying a pair a couple times after release but passed each time.