also arguably it's too ineffective considering how hard it is to open a restaurant. (because instead of harassing random taco trucks we should focus on other preventative measures, better visibility of food safety, better reporting and tracking)
sure maybe it's time for a "Let's Email" (after letsencrypt) service that handles reputation for email senders.
we already have certificate transparency logs, OCSP, CAA records, and all the fancy stuff, what's needed is something similar.
There are more than a few out there. No offense but if you would have had dealt with spam, you would have known that already.
the wonder of letsencrypt is that it does have the backing of Google et al.
Another way to look at it: In what world are you more likely to be able to cook your own burger: One where it's literally just McDonalds who can now control how people talk about burgers, or one where there's also other restaurants as well.