> You alpha geeks can but the other consumers can't.

Isn't it literally enabled by 1 simple setting in developer options on an Android device?

But it is. I installed F-Droid by visiting a website, so it's definitely possible.

Maybe you're talking about Apple specifically? Afaik, there's no way to do that on iOS (though I read a related article about it recently, I think it was here), so if you want that, petition Apple. There's no law preventing it given that Android devices can do it, so it's just an Apple policy, and you can always install apps through XCode if you want to.

> So let's say this law passes

In that case, would you expect the people who wanted this to actively create a means for its circumvention?

> So let's say this law passes BUT someone builds a really good open-source messenger.

> What we need is a law requiring some type of side loading.

You are asking the bad guys (passing bad laws) to be good (passing good laws). I do not think those expectations are realistic.