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.
I stay my point: something i can hold in my hand or private wallet that's real wealth and the wealth i can count on.
@OP, you want your money in the bank to be backed by gold or crypto before you can believe that you have money other than the number you see on the screen. Is that how bank operations in your state? If you want a real asset that you can feel and touch, then you can withdraw your money from your bank and load up the cash in your house so you can be seeing and touching the money anytime you want or you can also withdraw the money use it to purchase gold or crypto as you desire. Maybe with that, you can believe you own the asset.
One thing you need to know is that, if you have a bank account created in your name, what ever money you deposit into that account belongs to you, you have access to the money anytime you want as long as the bank is functional. The money in that account doesn't need to be backed by what you mentioned. If you need cash, the bank will give to you.