I don't think that's what is being said at all. I think what's being said is that if the future belongs to the next generation, it's in all of our interests that intelligent and responsible people do not simply give up and allow the idiots to dominate the future. In other words, we all have a stake in the coming generations and simply opting out because we find it somehow inconvenient is not a moral decision.
This is not to say that we all need to have kids, but rather, is to say that we shouldn't necessarily fault those who do choose to have them. Again, if the children are our future, it would be nice if at least some of them were raised by responsible, intelligent and well-educated parents.
Or, you know, not the party that is openly authoritarian and anti-democracy. We don't have to like Kinzinger's politics, but let's not be fucking morons and misrepresent the reasons why he's turned against his own party. That's good for no one.