This comment is a prime example of something that makes sense on the face of it because the rebuttal requires knowledge on how money actually works.

For example, you completely glossed over the fact most economists agree that, for money to have value, it needs to be a good:

1. Medium of exchange

2. Unit of account

3. Store of value

To achieve this, a currency needs a certain level of stability and to be accepted by the institutions you need to do business with i.e. governments. Money & Macro has some great videos on this topic. This one on China's attempt to replace the US Dollar as the reserve currency is a good starting point: https://www.youtube.com/watch?v=49iLl-V4xos&t=653s