The UK wants to reduce immigration dramatically so they are raising standards arbitrarily to exclude the spouses of many English people from immigrating. The whole story is here.
The U.S. has a minimum income requirement which I think is terrible, but it is far below the UK level of 25,800 pounds AFAIK. I don't know what the PPP median income is in the U.K. or much about the social safety net but I suspect that number is set far above what is necessary to ensure immigrant spouses don't become wards of the state.
The U.S. also issues probationary green cards like the U.K. proposal includes and I think lengthening the probation period to 5 or even 10 years might be reasonable because if the marriage is in good faith, what do you have to lose. But the policy isn't costless. If the couple has kids then the parent should be allowed to stay even if the marriage dissolves. I don't know if it is like that on the books but most people would agree that is how it should be. A longer probationary period increases the incentive to have kids as insurance against the marriage dissolving the foreign spouse losing his green card. It also creates the preserve incentive where a woman might cheat on her husband, he would normally get a divorce, but he'd lose his green card and this makes the choice more difficult if he is still on probation.
The "test of attachment" is retarded.
I'm pretty "hawkish" on immigration policy. I hate birth tourism, don't believe the 14th amendment covers people visiting or tourist visas or illegal immigrants, favor English as the national language, and believe the citizenship of "dual citizens" should be revoked. But these regulations strike me as pretty bad across the board with the one exception.