Seems they came up with a pretty good solution in the One UI update. A single finger long press will allow us to change the watch face. But crossing my arms no longer triggers it. Tested further by using a two finger long press and it does not bring up the change watch face option.
I would probably still rather have a face lock, with the single finger long press being used as a customizable quick shortcut. But still. I'm pretty content with their solution.