We don't need to do anything, the economy is already decreasing population. The dual income family has destroyed big families. It's very difficult financially to have one child and two is about the max families can handle. And dual income is necessary to survive now. Economy is getting harder and harder for everyone. The optimal strategy for families now is to put massive resources into 1 or 2 kids and hope they do ok in this coming automated economy world. Social security is on the path to collapse. It's not a giant savings account like many think. It's designed so current tax income pays for current retired generation. When the millenials retire, the system will collapse due to lower young population. But it's not just social security, the whole economy is designed like this. Population growth was a base assumption that is no longer true.