There are probably some context where “informed consent” is a sensible legal basis for processing data. But no-one in their right mind would freely agree to all this tracking that those pop-ups are trying trick you into. So instead of trying to make “consent” easier to give, just assume that is wont be given.

I can think of two or three entities I interact with for whom I might enter such a consensual agreement with. Neither are “sites”, and the web is not the primary way I interact with them, so a browser would not be to tool to maintain those agreements.