No way US has the most open immigration policy. I went through that "policy," all by the book. I also investigated other countries at the time.
1. US was the only country with no set criteria, other than near family members. There was no point system, no merit-based independent immigrant policy. H1B visa was (and is) the only way for an independent immigrant, other than special circumstances (like asylum, refugee, etc.). Australia? Point system. Canada? Point system. On a side note, H1B visas are in such a backlog, they are pretty much capped within a few days of new calendar cycle, where they can no longer be issued for the rest of the year. Open 3 days out of 365.
2. It took me 11 years to immigrate, all legal, all by the book. Canada? Would have taken 3-4 years. Australia? Similar.
3. Spouse gets nothing in US. No ability to work at all. Family unity, my ass. Spouses in Canada and Australia were allowed a working status, so family could immigrate together and continue working for a living, rather than falling on hard times.
Mr Professor has an overinflated sense of country ego. US immigration policy is no policy, it is a jungle, a mess. A capped mess. Eat or be eaten. My wife and I contemplated going around the system, having a child for immigration purposes before we were financially ready, but we persevered at time cost to us.
If US is an open policy, then camel through the eye of a needle should be considered an open policy.