As someone who went through the H1-B process and had my status threaten a number of times (downsizing), it was just a reality - if I lose my visa I go back home and maybe try again.
It never stopped me from major live decisions like buying a house.
Immigrating to a new country is taking the risk that you can’t stay. I accepted that when I immigrated.
No one would complain if H1B was a transparent and clear system (like a points-based immigration system). In reality its often arbitrary, with your visa status hanging on the political tides of the country, or how a visa/border officers day is going. That kind of unpredictability wasn't clear to me when I got the H1B and isn't any kind of well-defined risk you can accept before going down that path.
But it doesn't need to be so tenuous.
Emigrating to the Netherlands seems like a friendly walk in the park compared to the capricious bullshit that immigrants to America are subjected to. I'm ashamed my country treats people like this.
It's idiotic to make it hard for immigrants to get back on their feet, it's not like working immigrants cost money..., what cost money is to lose them to a competing country...
But in essence you're right anyway: immigration is a privilege, complaining about it is really unfair to a country that was never forced to take you in in the first place. The only thing we the immigrants and the host countries can do, is compete on entry condition, to bring the most high skilled, high asset immigrants.