Automatic authentication signature vs. EIP-712 message signing

While developing EVMAuth, I was surprised to find this thread from 2019 that seems to have just been abandoned due to lack of interest.

If Web3 app developers simply want to verify that a user owns an address (i.e. has the private key), why wouldn’t we want a mechanism to do this baked right into digital wallets that does not require human intervention?

I get that you don’t want your wallet just signing any old transaction blindly, but if there were a standard message format for this type of check, it would make user authentication trivial…and when you combine that with EVMAuth for authorization, it could render all other forms of auth obsolete!

Curious what others here think. What am I missing?