So what?

The culture dies if locals don't have children and the immigrants don't assimilate. There are already many pockets of micro cultures in the US and that's what the people in power are using to divide us already.

I'm increasingly convinced that the goal is to balkanize the US and establish a Network State guided by silicon valley, as described by Curtis Yarvin

The whole modern US culture is literally "immigrants who didn't assimilate" with small pockets of native Americans. From my outsider perspective there is very little common between techie from Valley, NY yuppies and a rust belt redneck. Adding some asians and mexicans just improves your cuisine ;)

You really are hitting the propaganda talking point bingo here.

It doesn’t support economic models in the long run, unless you start modifying the definitions of “consumption”, “growth” and “value created”. It also doesn’t work well unless you create some utopia where everything is automated for old people and they can live without support from the younger generation.

The problem has not been solved, and all western governments are hoping to delay the problem through immigration. This buys them time to see what solution Japan, SK and China can come up with, and copy that instead of taking risks with potentially abysmal results.

There is a huge line of people wanting to get into the US. Authorities can pick and chose whatever they need at the moment (highly educated tech professionals and scientists or cheap labor for manual jobs, etc.) and instantly "magically" get such people, already grown and educated at someone else's expense.

This sentence belongs in a dystopian novel, not in the real world where people have to live with the consequences.