all debt held currently held my moody's should be allowed to refinance

If the debt is held by Fannie or Freddie, it means the debt is held by the
govt. and backed by the taxpayers of the USA.

When someone defaults the loss on the default is suffered by the tax payers.
If everyone is allowed to refinance to today's rates, then the likelihood of
default decreases.

From DS News

> Moody's: Refinancing Is Key to Housing Market

If all of Fannie Mae's and Freddie Mac's borrowers paying interest rates
that are higher than the median rate were to refinance at 4 percent, the
savings would total $63 billion. While such an option would not bring the
total $63 billion in savings to fruition, Moody's chief economist, Mark
Zandi, says "even a fraction would be a big plus." According to Zandi, the
single most effective policy move for the housing market would be to
facilitate more mortgage refinancing.
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