Distribution. It's what copyrights are about. GPL and open source licenses are all concerned with terms of distribution. App stores and walled gardens are about controlling and charging rent for distribution. It's basically all about trade.

The web for software distribution is free or very near free in a lot of cases.

Your point about browser vendors monetizing their users is valid, but that is unrelated with distribution of software that targets the browser.

I choose Mozilla; I trust them the most of all of the browser vendors and I appreciate how they continue to drive so many web standards forward.