You're not "wrong" in your assumptions, but you neglect 2 important bits of finance, and the major one that's the first thing you learn even if you don't take a finance course.

1) Time value of money. You can't just say 50B in 20 years is worth 50B today...It's intuitive. I'll give you $100 today, or $100 in 10 years. There would be little reason not to take it now.

I agree "There would be little reason not to take it now". Because the time value of money erodes over time. However, the time value of lbs in the ground increases with time. So wouldn't it be wise to trade a depreciating asset, such as currency, for an appreciating asset, such as gold, silver, copper, etc?