The problems you described are specific to implementations, not the protocol itself. I have read all of the QUIC specs in full (since I'm working on an implementation) and have seen nothing in any of them that mandates a centralised certificate infrastructure (caveat: I have not read the HTTP/3 spec, perhaps you could point out the relevant section if its in there). Of course, the most common use case requires this, but in that respect it's no different to HTTPS.
IPFS uses QUIC as one of its supported transport protocols, and this works in the most common implementation, Kubo [1]. The spec for the QUIC transport used in IPFS [2] indicates the same certificate trust policy as for the TLS protocol [3]. The latter, in turn, relies on peer-to-peer authentication with automatically-generated self-signed certificates containing a libp2p-specific additional extension.
IPFS is particularly well suited to the use case of personal websites you've mentioned, as it's specifically designed to operate without any form of centralisation.
[1] https://github.com/ipfs/kubo.