When we think about "sound engineering" this is the level we need to start at, not "what features could we bolt on to core Internet infrastructure to define the problem away".
The people most avidly pushing DNSSEC for this problem aren't stupid. They're just smuggling in an additional premise: that the WebPKI itself is bad, and should be replaced with a DNS PKI. Seen through that lens, secure proof of domain ownership would be deeply problematic, as it would leave the DNS PKI with literally no reason to exist.
If you want to keep zone delegation, your proof of ownership PKI is going to end up having to solve many of the same problems DNSSEC tries to.
And the thing is, once you have a secure, automated way for websites to prove ownership of a domain, the necessity of trusting a bunch of third party CAs to validate that information for you starts to become questionable.