If we really want to address population decline, we have to reverse the reasons people are choosing to have fewer children. Which starts with policies aimed to give child-bearing aged adults better financial stability, affordable housing, and support -i.e. easily available, non bank breaking childcare (perhaps even free childcare), improved income / decreased expenses to make it easy to have financial security while also having extra bedroom(s) for kids, and longer, paid parental leave.
Whereas the existing housing crunch, continued downward pressure on median and lower incomes, bare minimum parental leaves, and high cost of childcare in the US discourages and delays a lot of people from having children.