Ah good point. But when you see SSJ2 Caulifla matching with SSJ2 Goku with ease even if she has reached that form like 2.37 seconds ago, you see that they don’t give a fuck, cuz Caulifla should be exhausted after three second of random punching while Goku would still be fresh. You could say that Goku was holding back but with this kind of argument you can excuse anything.
Ultimate evolution by default is completely equal to Super Saiyan 3 in terms of statistics. It is worth noting however that Arcosians can use their 100% power ability in Golden to make it even stronger. So a 100% Golden Arcosian by default is slightly stronger than a Super Saiyan God at a 2.875x increase.
Of course this all heavily varies based on server settings. You yourself can adjust these settings in the config for single player if you so desired.