You’re missing the point. It is “just” the act of downloading and installing, which were seen as normal things to do. However, by calling it “sideloading” they can then attach any meaning, any implication they wish. This is now something different and wierd, not something normal people do, does your mom sideload? I’m pretty sure the battle for control of your phone that you bought was lost as soon as we allowed them to call it sideloading.