Your point is valid, but there is a flaw in the premise. They don't need to pay off the $5 trillion in 20 years. They just need to be able to service it. If they can use that debt to bootstrap the company, as long as they can pay the interest and issue new debt, they can keep that $5 trillion on the books longer than either of us will be alive

I suspect if you go back to look at say, Microsoft's books from when they went public to today they have never been debt free