Well, first it will have an impact is our lifetime. It already has. But you have a point. But the idea is not to have no future generations. It's to have smalle

Well, first it will have an impact is our lifetime. It already has. But you have a point. But the idea is not to have no future generations. It's to have smaller generations over time. Perhaps 10-50x times smaller. This would requires a few generations to happen. Even by just having one kid 10x would be achieved in three or four generations. In theory. In practise it would create a lot of economical problems as well, because the economy would shrink a lot. We are currently not prepared for that and nobody knows how to do it. On the other hand it's a moot point, the global population is actually growing and even in rich countries it's at least more or less stable.