If these ETs indeed are us from the future, they may care about the Earth because they made a few mistakes along the way. Maybe they have went back in time to us to try and prevent this from happening.
Dan Burisch talks much about this as well in the Camelot material.
It is a tragic tale about how when the Earth shifts in 2012 it reacts to the looking glass technology and caused a rift in time and space which resulted in what those ETs are now. I know there is probably more info on this in another thread somewhere.
But from their point of view they seemed to be nice overall. They being us.
I am unsure of any negative agenda. I'm sure there are more readers here that could share their thoughts on this. However, overall, the direction the humans are going now is not good. So maybe we should change our ways in a hurry to lessen the blow.
Most races are humanoid anyway. So we are all related. Just from different parts and times of the galaxy.