If it makes you feel better, the owners of US treasury securities also do not want a debt-fueled collapse of the government. They are our assets as much as they are our liabilities.
Owners of US treasuries are: Japanese government, a whole bunch of rich Arab Middle East governments, Social Security, Federal reserve, and the Chinese government. With the exception of the last one, the other holders are political captives.
Incidentally, Chinese government stopped buying US Treasury instruments 2015.
All these to say that arguments that depend on freedom of choice ( like this is a free market, or for every seller is a buyer, or US treasury holders want this and that) do not apply to this situation. Which makes this situation so hard to predict.
