Lowest figures for medical debt, 20% hold debt, and 7% hold more than $1k. Ignoring that the remaining 13% may be>300, we'll say it's less. That's 13.5 trillion dollars potentially. Medical companies in the US are 1.34 trillion in size; they’re fine. 46% of Americans hold credit card debt. That's a potential of 6.4 trillion dollars if they forgave 4k/year. The top banks' combined market cap is $2.395 trillion. The medical companies handled a potential 10x loss; the banks can handle a 2.6x risk.