Well of course. As American citizens, its up to you to decide whom you wish have in your country. Its entirely acceptable even if you say one no should be allowed. I definitely won't make point on the lines of 'immigrants built America', its your decision. Nor am I saying that its the job of the US government to improve the lives of people over the globe. Though I believe even without others asking for it, or their consent, Americans are more than happy 'spreading democracy all over the world'.

But you can't stop any one living the way they want. There will always be people who will run/swim the extra miles, lift the extra weights, study the extra hours, eat ramen, do more than one job, walk/sleep in the cold, do the side gigs, moonlight their companies in garages. This is not slavery or anything. Slavery is stripping away people's rights without their consent, under the threat of violence. This just people wanting an edge over other humans. And regardless how you wish to live your life, there will always be people looking for that edge.

Lastly, I don't thing anyone living their life any way effects your standard of living. Your wages and compensation are decided based on how much effort your willing to put to get into a FANG. People who are willing to do that already make lots of money in a place like Bay Area.

The best thing about America, is the society goes lots of distance and makes it easy for people to do anything they want. So that at the end of the you are left with your own choice to make whatever life you want to. No immigrant is coming in your way of 'pursuit of happiness'

If you want to earn more money and want to know what's preventing you from getting it, you only have to look at the mirror.