>The term "sideloading" makes it sound shady and hacky
"side" refers to the fact that it's not going through the first party app store, and doesn't have any negative connotations beyond that. Maybe if it was called "backloading" you'd have a point, but this whole language thing feels like a kerfuffle over nothing.
Sounds like "sidestepping" i.e. doing something illegitimately or at least outside the normal path.
Language strongly influences how people perceive things. For example, people shown videos of a car crash estimated higher speeds and falsely remembered seeing broken glass if the crash was described as "smashed" or "collided" rather than "hit" or "contacted"[0].
"Direct installation" sounds neutral to me, but "sideloading" sounds advanced or maybe even sneaky.
I get where you are coming from. However, language like this matters when it comes to legislation. People outside there space will be guided by the sideload language to think it's just "something extra on the side so why should I care?"