How are Wikipedia articles like this protected against defacement and misinformation?
The key word is protected.
Note: I’m an ex-longterm Wikipedia editor and was the 2nd highest rank you can get without being employed by Wikimedia
First, the article won’t be updated to reflect current events. It will be kept a few days behind to make sure things settle a bit more. When people start breaking this rule, they’ll set it so that only logged in accounts with at least 10 edits can make changes.
When this starts to degrade, they’ll set it so only Extended Protected Editors can edit the page. These people mostly know how to behave; anything they add will require a reliable source (a well defined term: https://en.m.wikipedia.org/wiki/Wikipedia:Reliable_sources) and any edit wars will be handled in the discussion section of the page. You would be surprised how smoothly these things can go- at this point, everyone knows the ins and outs of Wikipedia rules.
But, sometimes that’s not enough. They may either delete the page and give up, or fully lock down the page so only administrators can edit it. I’ve never actually seen administrators edit war eachother, but I know it happens. Generally at that point you only have people with 10+ years editing experience chiming in (as anyone else would make a fool of themselves by not knowing Policy 18 of some random WP:LINK).
This is all off memory since I stopped editing like 6 years ago, but high profile editors will spend a long time monitoring this page. The Wikipedia rabbit hole is one of the deepest places in the internet.
