If 10 People share something with the same color to you, how would that be better?
Or do you want to automatically get different colors for each calendar in one account?
If yes, it should be possible to choose the same colour manually.

I think it's a better option to take the color from the original calendar, as it's not usually duplicated here. We have, for example, 10 shared resource calendar for 100+ users. If everyone adjusts the color (because everything is gray), that's a big waste of time. And it only occurs at the beginning of calendar sharing when it comes to duplication.