You just said the same thing you said previously with more words and a bunch of RFC cites. If you store your PGP key in the DNS, then the entities that control the DNS can control your key. That they are "public keys" is immaterial; the point of a public key stored in a public ledger is that other people can rely on that key to safely send you a message, which they clearly cannot do with a key stored in the DNS.

Even if you believed DNSSEC is a good system --- nobody should; it's bad, and moribund --- a secure messaging system with end-user keys anchored in DNSSEC-protected records would be an incompetent design, on its face, simply due to the basic core architecture of the DNS and DNSSEC.