But you did call it a cost, of $250B per year. That means that it is cumulative, for example it would mean $500B over two years.
It is neither a cost nor cumulative.
I agree with the rest, though. Eliminating the backstop ASAP is a priority to Treasury both for the budgetary reasons you point out, as well as reducing taxpayer exposure to a potential downturn that sends FnF under again.
also as portrayed to Mr. & Mrs. Voter at election time. Remember the sequester?
If that were true in this case, I would have expected an FnF resolution in advance of the midterms so that Trump could crow about his administration having reduced the federal debt by $250B.