It's pretty simple. Investing in crypto currency is the easiest form of investment without much regulatory procedures unlike the centralized government owned investment which requires excess documentation. For Crypto investment all one needs is just the patience to buy a coin and hold until it begins to appreciate
That's very much correct and may be prime reason why majority of crypto investors are mostly millennials. There is no age restriction nor any documentation required unless you are going to open a crypto account on KYC based exchange. Investing is easy but its equally challenging to earn profit in crypto, since its volatile, unregulated and mostly has no fundamentals.