it seems like all this infrastructure could be replaced by a DNS TXT record with a public key that browsers could use to check the cert sent from the web server. A web server would load a self-signed cert (or whatever cert they wanted), and put the cert's public key into a DNS record for that hostname. Every visit to a website would need two lookups, one for address and one for key. It puts control back into the hands of the domain owners and eliminates the need for letsencrypt.