Adding a few pop-ups that almost everyone ignores or clicks at random to see them closed (I know I do) is different than having one of your main money-making ecosystems forcefully changed in a matter of a few months. (I'm thinking mostly about Apple here).

Its not 'a few pop ups'. GDPR has far reaching implications which every major company and even every prominent website implemented. From providing you your data when you asked to deleting your data when demanded. This also includes choosing what you allow to be tracked.