No it's not. Immigrants tend to adopt to native sub-replacement birth rate and bring their elderly parents to live in US and often make use of social security.

No it's not. Immigrants tend to adopt to native sub-replacement birth rate and bring their elderly parents to live in US and often make use of social security. Even to the degree that they have children, children take two decades to enter the workforce. Bottom line, it's impossible to solve US labor shortage with any reasonable immigration levels under current policies. Unless you want a Dubai style system where only active workers are welcome and those don't get benefits of the citizens.