You don’t know what you are talking about.
Living in the US without permanent legal status is exactly what it says. To state it more simply - they have temporary visas that have to be renewed occasionally.
Secondly, immigrants do not necessarily apply to be Americans and many do not want to be Americans.
Thirdly, legal immigrants pay taxes and comply with the laws.
I’m not defending or condemning anybody, I just want to put facts straight.
People here on temporary visas are by definition not immigrants.