It's more complicated than just that: the sites are designed that they just don't work if the browsers don't show them the cookies they saved before. And there'

It's more complicated than just that: the sites are designed that they just don't work if the browsers don't show them the cookies they saved before. And there's the whole story about the "third party cookies" and on today's pages there is often much more "third party" content than anything else and there are often dependencies on third parties to even see the content. So to be able to somehow reduce the exposure, while avoiding every time clicking for a long time to accept and reject all the conditions from some big sources like Google (where in Google case is anyway not possible to affect much in spite of what one clicks, as the EU sees), one way would be to construct the compartments, i.e. keep a few "related" sites inside of something that the sites see as a unique browser. Then one has to maintain as easy as possible all that, to appear to the sites as "unique browsers", while using one. Firefox has the "containers" for that but the use of them is, as far as I've tried, a bit clumsy -- it's still quite hard to manage what happens in which container -- there's too much manual work to do and it's easy to make errors, even if the user has the general idea of how he'd like to compartmentalize his surfing. Chrome, of course, is less interested to enable their users to hide something from Google. And Firefox is also not guaranteed to ultimately do exactly what the user would like the most, especially as the users for years flocked to Chrome, directly showing that they "don't care" giving Google what Google wants, as long as it's more "convenient." The structure of Mozilla entities is also somehow made to induce some decision problems which became more prominent with the time. It doesn't seem that the "free market" can solve this, and EU intervening long-term could work, if they manage to be consistent enough and manage to enforce that. But it takes a lot of time.