If it were trivial for anyone to disable unwanted behaviour in browsers, you wouldn’t see so much EU legislation being passed, forcing websites to make useless disclaimers.

On the one hand, browsers have a long history of breaking security principles. On the other, the web has been the most vibrant platform for enhancing user experience; the same commercial interests that RMS criticises have caused the world economy to flourish like nothing else.

If Emacs had somehow become the most popular VM in the world, I’m sure we’d see a lot more skepticism of it.

I do think browsers are more secure than Emacs today, because of the pressure of popularity.

But the criticism of the web being captured by commercial interests applies just as much: you are not ultimately safe from the government when you roam the web, because the technology is largely controlled by few actors.