I learned enough about security years ago that there's basically zero chance you're secure and almost 100% chance someone is watch everything you do online.
"Watching" is doing heavy lifting. "Able to watch" or "being recorded, along with terabytes of parallel information from others", is more apt. Actually discriminating the signal (communications from a desired target, or about a desired topic) from noise is the problem with your "nothing you do will stop them" theory.
I forget where I saw it but there’s an old adage along the lines of “even if your computer is unplugged, in a vault, with armed guards, it’s probably not safe”.