As someone who has used chromium incognito as a crutch, 100% this.

Browsers need to be seriously redesigned with privacy (aka security) in mind. The javascript execution environment needs to be gutted to remove security leaks like screen/window size. And incompetently (/maliciously) designed APIs like websockets need to be thrown right out.

The main browser makers get huge incomes from advertising. That's not going to make them want to spend a lot on protecting users from advertising.

Maybe in Chrom*, but not in Firefox.