It still matters. Is it as effective as advertised? Not really. But it's still doing something. Privacy and security are never a one off solution, but a group of methods/tools.

I also feel you missed my point in my original post. My point is, using "incognito" from a browser from a company like Mozilla is better than using it from a browser made by an advertising company. One of them has an incentive to screw you. One does not. And to reiterate, I never said it was a perfect solution. It's mitigation.