They are too redeemable, I just redeemed a five dollar bill for a Mexican pizza, a couple of tacos and a drink.
Value of all goods and monies are subject to change, whim, and the perceived value of others. Gold is of no intrinsic value to me, can’t eat it, too heavy to put over my head, blunts easily when fashioned into a spear.
Get used to the fact that values almost everything is only worth what the next guy will give you for it.
Gold maintains its purchasing power.
That is why our founding fathers referred to it as "money."
Paper dollars are not real money.
They are IOU's that at one time could be exchanged for real money. (gold/silver).
The paper bills do not even state that anymore.
They are merely pretty pieces of paper that may or may not be accepted for exchange tomorrow.
An ounce of gold in 1895 would buy you a handmade, tailored men's suit - same as it will today.
You could buy an ounce of gold for $35 in 1895.
35 paper dollars today will not buy you an ounce of gold, or the suit.