> Ok, non-tracking ads. So, until tracking ads stop existing, these will continue to bring in significantly less money.

That's fine by me.

> It is extremely valuable to know which users are interested in your product. Advertisers want this.

Advertisers aren't entitled to everything they want. While they've been getting away with it, they're certainly not entitled to cause harm just because it will make them more wealthy than they would be otherwise.

> This product from Mozilla can be seen as a step in this direction,

I agree, this product from Mozilla is a step in the direction of giving Advertisers what they want: higher profits through the invasive tracking of users.

The fact that it allows advertisers to outsource the user tracking to yet another third party does not make it "less tracking". It may not even keep our data out of the hands of advertisers if they're able to use the information they're given along with additional data to re-identify individuals. Differential privacy may reduce the odds of that happening, but there are no guarantees.

> It’s not like everyone with a site is putting up advertisements for fun.

No, they mostly do it for profit. It's not like everyone with a site full of ads needs those ads to keep the site running, or that those ads couldn't be profitable without invasive tracking. It's not mechanical, it's usually just greed, selfishness, and laziness.

If someone wants ads on their website it's very easy to sign up with an ad network that is harmful to the people visiting your website. It's easy to not bother making sure those ads aren't pushing malware, or spreading harmful lies, or promoting scams. It's easy to just collect your money and not worry about who is being hurt by your choices. It's easy to say "everyone else is doing it!", but the fact that it's easy doesn't stop it from being wrong. Ads aren't going away, but we should insist on them being less harmful.

Yes, I fully understand the reason for tracking: profit maximization. Isn't it interesting, though, that enormous swaths of the advertising world manage to be profitable without engaging in tracking (because it's not possible, but that's beside the point)?

> This product from Mozilla can be seen as a step in this direction, leveling the field at a “less tracking” level…

Sure, that's a reasonable view. It's certainly Mozilla's. My view, though, is that it instantly transforms the browser away from being a "user agent". It means that instead of an ad company tracking me, my browser is, which means that the browser itself has become an agent for others rather than for me.

It's just moving the tracking out of the hands of ad companies directly and into the browser. You could argue that's better, but it's still tracking me. It puts the browser into a position where it is adversarial.

That, at heart, is why I will be sure this stays disabled. To do otherwise means that I can't really trust the browser and will make the web even smaller for me than it has already become.