If you want to come here to sit trading at home the whole day, expect to bring a bag of money (I think the minimum was about 200k euros, not sure though) and you will most likely be required to setup a company (and get an official income from that, you also need to pay taxes, need various insurances). Else there is little chance to get a staying permit. You will most likely be required to learn about Dutch culture and required to learn the language.
Do note that Dutch banks are not happy with opening a bank account (you'll will be needing one) if you're involved with cryptos and that you might be required to hand over proof where the cryptos come from (they can suddenly block your account, freezing all funds in there).
Visiting the country as a tourist is one thing, living here is another.
What do you mean "to bring ~200k"? Didn't understand that part.
Do you think we will let everyone come here without a job or some sort of income? If that would be the case, the country would be flooded with people needing financial support (social securities) without any benefit to the society itself. I think most countries have such rule.
The exception to this is people who are hired by an already existing company or institute (need to show working contract), or refugees (need to proof that their reason of seeking asylum). In both these cases, people are expected to return to their own country when the work ends or their reason for asylum is not valid any more.
Another exception are people from the EU (free movement of goods, people and work between countries)
