Yes. I think this is probably the only really correct answer. Dollar is in the head.

I would add that not only now, but also in the future. When there was a parity between euro and dollar, one euro could buy you one dollar, but it was not a dollar.

And physical bills might not be available, it's not a question of value, but liquidity. In Panama or Argentina, papers with dead us presidents are in short supply and people have to use another forms of usd.