“Install” includes installing from an app store no matter how closed down and exlusive. The correct term would be “install from other sources than an app store” which is just clunky. Calling it “sideloading” won’t change that nor will calling it “your mom”. Considering how many corporate-speak terms are in use and how many braindead abbreviations and terms shortened to a word’s last syllable -completely distorting the original meaning- generally are in use, the term “sideloading” is pretty irrelevant. Either lose your mind listening to the bullshit people permanently are emitting or just live with it…