> Yes, there is: we all collectively decide properties of the world we'd like to live in, and we try to guess what kind of world future generations would also like to live in, and then we call those actions that ultimately improve those properties "good" and those that lessen those properties "bad"

First of all, who are "we"? Second of all, you just proved my point, unless you want to redefine "objective" as something that the majority accept. Also, why are those properties desirable? Because the majority prefer it? There would be no objective good or bad, then—it's just the preference of the majority.