https://en.m.wikipedia.org/wiki/Carbon

will open in mobile format. But getting the user agent is trivial, and so wiki should be able to easily redirect to this on a non-mobile device:

https://en.wikipedia.org/wiki/Carbon

But they don't, and since they're one of the most-visited sites in the world, I assume there's some really good reason why they don't bother. Anybody know why that might be? Is there some sort of esoteric security thing that sites have to worry about? Do they just not want to have to do the work of serving one page and then immediately switching to the other? Or is it something else entirely?