Refi’s work when you have cash or equity. You dont get to refi a house that you owe 750k on that is now worth 550k without money on the table.
So the Alt-A ARM’s from say late 03-now are underwater unless they threw down a real DP, and 4.5% fixed is a pipe dream for them. They will hold till interest rates go back up, then they will fold same as they would have anyways. That is unless the Fed manages to hold interst rates down to historical levels for the next decade or so to let wages catch up.
Basically they are just making you wait longer for your house.