MediaWiki has a mechanism called Pending Changes, where edits are held from public view until an officially-designated reviewer editor signs off on the edits. This is the sort of endorsement already built-in and in active use on Wikipedia, and it leverages the reputation of a trusted user to "endorse" possibly disruptive edits.
I'm not sure how a wholly external PKI could be any help in "endorsing" edits. A user's ETH wallet has no relation to their reputation or trustworthiness on WMF sites.
Wikipedians also use something called a "Committed Identity" which is a cryptographic proof of their identity, which can be used to recover an account if credentials don't work. Since it's encrypted, it doesn't amount to revealing your real-life identity, it merely provides a mechanism for them to verify it with your cooperation.