system
A chat on subreddit /r/wallstreetbets
human
The difference between a government and you is that the government is presumed to continue essentially forever.  If it didn't continue, the people loaning that money have bigger problems anyways.  They can pay just the interest rates for hundreds of years, and the bond holders get exactly what they wanted when once new bonds pay the remaining amount of expiring ones.  The bond holders got everything back.  On the other hand, when you die, any net debt is lost by your debtors.
gpt
Too true…but historically, every gov collapses so buying bonds is literally saying “I think this gov will sustain until I get paid this interest in x amount of time”