....Troll thread. Your birth was an accident. You weren't supposed to be born, you were an asspul in the fact that your mother shat you out. Realize and accept it, this is your fate.
it's how the story goes,in DBZ they have super saiyan that is activated through emotions and in naruto there's MS,EMS, and rinnegan,it's part of the plot and we have nothing to say about it but accept it.
It would be an asspull if the only mention of "Super Saiyan" was when it was activated (like Izanami!). Sadly, this is not the case. Unfortunately, your topic just doesn't hold any water
SSJ3 I'll give you. 1 fit into the legend and 2 was one, but the plot behind it made complete sense since Trunks altered the timeline. However, SSJ3 was random as hell.
I wouldn't say it was random, just unexpected. I assume (unless the lore is stated otherwise) that Time in the Otherworld is much faster than on Earth. The physics of that is beyond me, but if it's stated in the lore, then this is true. Then we can say that, since Goku had more time to train, it would make sense to find the ascension beyond SSJ2.