A married couple has to file a US federal return as nonresidents aliens (they are not US-persons). They have a US joint bank account, one of them has a high-income job and the other is unemployed and has no income. When they were residents, they could file a single joint return as "married filing jointly", which was favorable to them tax-wise.
Now, since they are nonresidents, they can only file as "married filing separately". Then, the spouse with the high income has to pay much higher taxes than before, and the unemployed spouse does not pay anything and does not get anything in return.
Is this right, or is there any benefit that I am not considering?