The most dumbfounding thing in all of this is the number of people interacting directly with Jimmy Wales on twitter and having no sense for how wikipedia works or why. It should not be surprising that a company webpage or even the CEO confirming the fact are insufficient sources. If wikipedia did accept this, they would just be a place for people to make self-reported baseless claims. There's already a place for that, and it's the platform they're responding on.
Wikipedia has an interesting problem. How do you build a large corpus of generally true information? Their solution is to offload the work of verification to journalists and academics, who are held liable for their statements by the institutions they work within. This is why wikipedia is a tertiary source. Primary sources originate some piece of information, secondary sources investigate and verify those primary sources (verify being "they said that" not "it really happened"), and tertiary sources aggregate trusted secondary sources. All of the people in the twitter thread (excluding Jimmy himself, of course) seem completely unaware in this system, and while I too would be interested in more "modern" approaches, don't seem to have thought about this problem at all.
Journalism and academia are both on the back foot these days, and it seems unlikely that we will see a big resurgence in funding for either. Without them, I don't see how wikipedia can continue to outsource the problem of verification.