What is a Van Gogh painting worth today?

it is all about what we think it is worth and of supply and demand.
someone creates a coin. They create x number as supply (totally made up). And a starting price.

This is why it does not matter much how big the supply is. Ripple and others can go higher than 100$. There is absolutely no real relation between the world money and market cap.

Take all art in the world and tell me its market cap. There is no limit, limit is what people think it is worth. And since cryptocurrencies which has no underlying asset etc, it could be compared to art.

Some coin has a real usage, some has none but right now it is still only about what we think it is worth.