@kalymmenon Great question. Most likely it goes back to "old English", when most people wrote in script, or cursive, and the W was formed by putting 2 U's together. Thus, a "double u." I agree that in today's world, it is kind of bizarre or a little backwards, but that's what the letter is called.
(RarelyCharlie's video might cover this. Unfortunately the link didnt want to work for me.)