Doing content signature verification securely would require all the same "crazy crap" that HTTPS does (certificates, CAs, OCSP, ACME, etc). The PKI is the hard

Doing content signature verification securely would require all the same "crazy crap" that HTTPS does (certificates, CAs, OCSP, ACME, etc). The PKI is the hard part; once you have that there's very little reason not to encrypt as well as sign.