Firefox and Safari have disabled third party cookies years ago, but chromium based browsers still have them on.
And then look at Google's "privacy sandbox proposals, that aim to replace third party cookie functionality. They have largely been rejected by Mozilla and Apple, over privacy concerns.
Firefox still accepts 3rd party cookies by default. They've made some moves to reduce reliance on them. Sadly privacy zealous prefer the perfect over the good, so won't get either.
It's everyone else who wants to keep them around.