You hold nothing If this money not backed by something real or atleast with cash.
The BONDS treasuries not something for sure but they are more like coupons wich show's how good situation the goverment and other people are to keep value of money.
I told my own bank show me stablecoins, cash,or cryptocurrency or gold equlaint with money i have otherwise i own only numbers wich doesn't mean anything just the numbers on screen.

It's mature way to look finances i don't want to my wealth backed by bonds coupons it's speculative and we never know If they keep holding any value at all.