The argument you made was that copy-and-destroy is not bad because a world where that is done is not worse than our own. In turn, your belief that it is not worse than our own is, as far as I can tell, based on the belief that you can compare that world to our own by comparing whether it is good for the people who remain alive, and ignoring whether it is good for the people who are killed. This implies that the fact that the person is killed doesn't count towards making the world worse because being dead, he can't know that he has been harmed, and because the other people don't feel the loss they would feel that goes with a normal death. This amounts to blissful ignorance (although I suppose the dead person can be more accurately described as having 'uncaring ignorance', since dead people aren't very blissful).

Check out Argumentum ad Populum. With all the references to "most people", you seem to be committing that fallacy so often that I am unable to identify anything else in what you say.

Pointing out that your definition of something, like harm, is shared by few people is not argumentum ad populum, it's pointing out that you are trying to sound like you're talking about something people care about but you're really not.