What were the old rules?? I once knew them but they have faded over the years in my mind. I’m afraid they have faded on the immigration books as well.
But I recall no one in the US could apply. You had to apply at a US consulate in your native country. There was an income requirement meant to assure you would not go onto the government dole. There were strict background investigations that covered work history, criminal, moral turpitude, financial history, and more. It was tough and the process took anywhere from 2-5 years. But in the end the US received a first rate immigrant,
Back in the old, old days you needed a US citizen sponsor to vouch for you and say you would have a job when you arrived. The Quakers sponsored lots of people because ... Quakers. Most of my family came over from Ireland in the 1800s under sponsorship of the Quakers. I think in practice, once in the country the Quakers didn't actually do anything to employ you so go find a job or starve to death, it's up to you.