I think Real estate and Gold are safer but Cryptocurrencies can bring a lot of profit if you have a exactly choice. For me, i only invest in cryptocurrencies 30% my saving money.
Yes both of them are safer because it is existing more than a decade and people know how to use it. But people in crypto world are getting use of it so we see in the near future what are the real uses of bitcoin and not only for trading and buying stuff online.