Another reason immigration (legal or otherwise) is rather important... we don’t make enough babies, and haven’t since the early 70s:

Overall, the total fertility rate for the United States in 2017 was 1,765.5 per 1,000 women, which was 16% below what is considered the level needed for a population to replace itself: 2,100 births per 1,000 women, according to the report.

[snip]

The report also showed differences in total fertility rates by race: Among non-Hispanic white women, no states had a fertility rate above the replacement level; among non-Hispanic black women, 12 states did; and among Hispanic women, 29 states did.

[snip]

For instance, between 2007 and 2017, total fertility rates in the United States fell 12% in rural counties, 16% in suburban counties and 18% in large metro counties, according to a separate CDC data brief released in October.

Additionally, provisional data on births that the CDC published in May noted that the nationwide total fertility rate “has generally been below replacement since 1971.”

As Boomers continue to age out of the work force, having no one to replace them is going to hurt the economy. Just ask Japan.