For the vendor (non-)consent thing - Consent-O-Matic provides an appropriate framework.
(Whether such a side would even care about the preference/consent is another matter entirely - I’d suggest a throwaway browser identity and cookie auto delete for a start, anyway.)
Creating rules has a bit of a learning curve the first three or seven times, but I find that more interesting to do than go through a hostile/dark pattern cookie dialog or such the third time.
Hm, maybe the appropriate functionality from CoM could be re-wrapped as a TamperMonkey module…
Web automation for the masses 😱
… Which means that businesses are making ‘too much’ money on top to sink into such endeavors, no?