Which of course means its closer to a form of enlightenment or enhancement of his mind than a transformation. Given that Whis talks about gods of Destruction in general trying to achieve this state, I think we can take it as given that it something anyone can learn seeing as how GoD's are very diverse biologically speaking. Also: it makes sense from a standardization perspective on the gods part of designing life in general. you design something like Ultra Instinct into all beings and your Angels can teach all your GoDs a universal power up of incredible power because its based upon minds rather than bodies.
and given that Vegeta talks about achieving power his own way and achieved Blue 2 completely consciously by thinking of Cabba and his promise, which is as far from Ultra-Instinct as you can get, that Vegeta didn't get it. Thought and Ultra-Instinct are things that are inherently opposed, as those attacks being weaker are because Goku thinks too much about it.