In that case, would it not make sense to have metadata associated with a particular section, detailing the final consensus and how it was reached? Kind of like a comment describing a non-obvious section of code. Otherwise you have the equivalent of telling someone "Before you modify this code, look through the entire git history to see why it's the way it is today".
Yeah, there have been some discussions of that, but nobody has put together a MediaWiki plugin to do it afaik. Better annotation of regions in general is a longstanding wishlist, so discussions or even citations (or requests for citations) could be attached to a region of text. But then there are problems like how to handle annotations and arbitrary editing/splitting/moving of regions.
As a low-tech solution, you can actually put HTML comments in the source code, which people occasionally do, but it doesn't seem to be a very well-known option. <!-- Do NOT change birth date to XX/XX/XXXX, see talk page --> kind of things sometimes appear in the source. I haven't seen them used for longer discussions, though, just one-line "hey, watch out before you do X" things.
On contentious articles with a long history of debate people will sometimes write a summary on the talk page, so you don't have to read through the whole history of the discussion. On most articles, though, the talk page isn't huge, so I find it easy to glance at before making changes.
If you have a problem with experts disagreeing about facts, arguing over them, reaching a consensus, and then other "experts" starting up the argument again - it really sounds like you're doing a poor job of communicating the researched consensus in the relevant article.
When that sort of stuff happens, I think you should make sure the incorrect information is referenced in the article as a misconception, or just have the correct information associated with citations. False information should only be erased if it is not "in the wild", so to speak.
