You have missed the point. This is not about whether or not there is an afterlife. This is about getting to the root of the disagreement, which is not the sin

You have missed the point. This is not about whether or not there is an afterlife. This is about getting to the root of the disagreement, which is not the sincerity or disingenuousness of the slogan "think of the children". It's about the weight people place on avoiding certain kinds of moral transgressions, and the fact that whose who do believe in an afterlife almost universally believe it is eternal.