It depends very much on what sort of future you are looking for and where you want to live. I Reckon a few bitcoin is enough for most people. Third-world country bitcoin users could even go far with just 1 bitcoin perhaps even less. I mean what do you want? Do you want to eat like a king every day and have a fast car and a large house? Or are you ok with things being somewhere in the middle? Additionally, some people don't particularly want to be rich and accept where they are. This is true since many people are given opportunities to earn more profits yet they pass them up.