I have really come to dislike the term "virtue signaling," since it seems to just be a more socially acceptable way of calling your interlocutor a sissy for caring about something. If pointing out the troubling moral implications of following a line of argument to the end is "virtue signaling" then the semantic space occupied by the word is so broad that it's meaningless.

As for the food supply stuff: animal populations can be constrained by factors other than food supply, particular when we're talking about a population which is capable of reason. You yourself seem to acknowledge this when you propose offering condoms, which would be a nonsensical suggestion if you truly believed that the only thing affecting population size was food supply. Therefore, I do not believe it is necessary for the sake of the planet to deliberately allow people to die of starvation.