Just like this anon said, it's the contrast between canon Hux, genocidal (presumed) sociopath General of the First Order, and the floofy milkshake bar barista that is Pink Haired Hux. Holding your favorite character up to a funhouse mirror via speculative au (in this case, what would a Hux who rejected FO propaganda act like?) is a great way to fully appreciate their canon incarnation.

And then sometimes... Sometimes you just want to see Vader riding a unicorn.