It's really just who they're trying to appeal to. Walrus is going after the candle in a dark room crowd. Boss is all about practicality. Earthquaker is about being quirky and different. Wampler is courting Nashville professionals and sort of country boomer types.
I like them all.
If you ask me though the most beautiful pedals are Boss pedals because there is a consistent logic that holds true through both function and form. They're like if Mr. Spock designed pedals. There is everything you need and nothing you don't. Everything from the sound to the knob layout to the enclosure itself is thought through to be elegant, easy to use, durable, and definitive. For example, they call their chorus pedal "Chorus" and they just put it on there in huge black letters. To me that's awesome and cooler than any cute graphic. I have lots of pedals with cute graphics mind you and I like them a lot. Sometimes a cartoony graphic can be part of the function because it inspires you to play a certain way. But I also love Boss's machine-like disregard for any kind of cuteness or preciousness in favor of neutral, logical practicality.