People who know WTF they are doing have plenty of privacy and can operate with impunity online. This requires a solid general understanding of all hardward/software layers.
Unfortunately that is a somewhat small slice of the population.
If you are still running microsoft's horrific jeetcode OS, you're probably not going to make it anyways.
But the fearful proclamations of "nothing you do on a computer is private" is just not even remotely accurate. People throw around technical buzzwords like TPM and so on without knowing WTF they are talking about. It's all so counterproductive. Just the usual fear porn for clicks.
If you setup Tor browser, and only use it for anonymous posting (ie. don't log into fagbook with it), you will be FINE. Nobody is going to "catch" you doing anything. The only thing the feds are good at catching is AIDS when they give each other blow jobs all day.