Visas expire. An asylum claim can be successfully processed by sending the applicant to a country other than the one the are seeking asylum from.
Asylum does not mean “remain in the US.”
To apply for asylum, you have to be physically present in the United States.
The Trump admin has mostly eliminated asylum for people who come by land. Now they’re punishing people who flew in legally on visas. It’s clear that they no longer want there to be any “right way.”