That doesn't work because you have to explain what you're asking for.

If the banner's not required, it ends up saying stuff like "we'd like permission to share your data with 0 partners". Ever see that?

The fact is most website operators want to (or agreed in ignorance to) use your data for non-essential purposes

Perhaps someone could publish a clear A/B test on how many views/conversions you lose by having a cookie banner?

Or they had their site developed by an agency and the cookie banner is just part of their standard scaffolding for a new site.

Let businesses who don't know what they're doing be outcompeted by businesses who know what they're doing.