This is a fair point. Treating things like Social Security and Medicare obligations as unfunded debt is akin to me declaring that I have a large amount of debt

This is a fair point. Treating things like Social Security and Medicare obligations as unfunded debt is akin to me declaring that I have a large amount of debt because I have to pay for food and clothe myself from now until I die. It's money I will pay, most certainly, but it's only an obligation to myself to sustain my life at some reasonable standard. Much like Medicare and Social Security, it will be paid for with money I earn in the future as I live my life.