I’m not saying they wouldn’t be able to exist though. I’m saying you wouldn’t be able to use them. Firefox does not have the market share to be able to force change there, they’d only be making the experience shittier for their users. You’re welcome to turn the feature off if you don’t like it.

Ad supporters are wrong about this as a blanket statement. There are tons of useful sites that exist, many for years or decades, without any advertising at all.

Some sites would go behind paywalls, some would cease to exist, and some will just run nontargeted ads, but some would do none of those things.