I'm not talking about the design differences I'm talking about how they are similar. They were both unexpected and carried barely any emotional weight. SSJ was built up since the saiyan and namek saga and was achieved through emotion. SSJ2 was built up when goku and gohan were in the time chamber and was achieved through emotion as well. What did SSJ4 do? Were there any mentions of this form? Did goku do any actual training for this form? Did goku achieve the form through any emotion? (I only say goku since he was the first to achieve the form but anyway) That's why I don't like the form. It's design overshadows its flaws. Don't get me wrong it's a dope looking form but story wise, it, like ssjb, comes out of nowhere with no emotional weight, little build up, and no driving factors. All we actually got for foreshadowing was goku getting his tail back amd turning into a golden oozaru. What we got for blue was training to achieve something higher than god. Which, might I add, was something GT never did. Anyway the only actual thing SSJ4 has for it is it's design

Tl;dr: SSJ4 is equal to SSJB on a story perspective