Earlier quoted context omitted.
It's better for a browser feature the user has some control over to be the implementation point for this than incentivizing site owners to come up with novel tracking strategies.
Except this is not how things work. All you are doing is giving the advertisers another tool to track you, it won't magically make them stop using all the other ones.
The online shopping businesses really isn't interested in privacy, I don't even really blame the adtech industry for this one. The companies running the ads and retargetting campaigns want to know who clicked on what and when. Anything less will trigger a frantic search for ways to evade privacy improvements.