In Nakamoto's system they inform them that they own xx pieces of "chain of digital signatures". Which is stupidity never seen in human history. Because that chain is only one, it is freely available to everyone, and one can make as many copies of it as they want.
Oh you finally understand that a bitcoin is actually linked to the blockchain and therefore a unique thing that you can actually be in control of. Only because it did not exist before does not mean it is stupid.
Yes you can also make copies of a dollar bills as many times as you want, but it will not be linked to the original thing as you said yourself before. It will be worthless.