A former Apple person reminded me that the new major version iOS must ship on the same day as the new hardware, as the new hardware (this year, the new iPad Mini, and iPhones 13) will not run iOS14. They are developed in lockstep with the next OS and will ship with it, and cannot ship without it.

The software is going out the door alongside the latest version of their biggest money-making product.

Note well how quickly 15.0.1 was released.