Ok, so if the stones are demonstrated to be sentient. Of -the greatest artifact in the universe- that certainly makes sense..
WHICH MEANS, if the stones Didn't think culling half of all Lifeforms in the Universe was a good idea, they wouldn't have allowed it, just as how the Space-Stone banished Red Skull to be field guide to the Soul-Stone (Forever)...
So.. Clearly, that means, from the perspective of the Stones, Thanos was doing the right thing ??
Then , the Oldest non-god character of MCU and the Greatest artifacts are in agreement.
Wouldn't it then be mere human-life-hubris to purport that WE (life itself) know better ??