In terms of cryptocurrencies, I believe that investing is better, but "decade" is a very long period of time. You should have a couple 10 million dollars in order to make enough money by investing for such a long time (if decade-investment doesn't mean anything else, I'm not sure). But, I think there is no such thing as better. Which one is fitting you better, this is important. It depends on your capital, your lifestyle, your habits, your daily occupations, your risk appetite etc.