I've lived in both countries, and if I could, I'd swap my Canadian citizenship with an American, any day. I've tried for years to find a way to get permanent residency in the US. It is unbelievably difficult. And I'm not some knob:
And I'd be very confident that I can get a well paying job in my industry (no it's not tech, healthcare, or trades, but still constantly complains about needing skilled people). But there is really no way. Companies are not going to go through the trouble of trying to sponsor you (this is really mostly just done by big tech companies looking to buy cheaper labor).
The pathway is just incredibly hard. Versus the UK just rolled out the red carpet and I hardly had to do anything, lol. I don't know why the US makes it so hard for people from allied countries with a high degree of education and proven earning capability to immigrate. They could easy brain drain so many countries.
The other people is going through an investor visa, which is very, very expensive. Ironically, you get a lot of people from not so friendly countries taking that route.