Read any SS Trustees report. It doesn’t have “money”, it has debt instruments (bonds), which are essentially a document saying “we the government owe ourselves a thousand dollars”. You can print those all day, it’s only sourcing that money that has any kind of direct consequence (taxation, inflation, etc.).
And yes, that does raise an interesting question of, what did they do with the actual money we paid into the programs, if the only thing in the trust fund is bonds.