Lets say I want to buy bitcoins today and store them for 20 years to use a my retirement fund. Live comfortably, but don't need to buy a yacht or anything. How many do you think I would need to buy?
We don't know what will happen 20 years from now, maybe bitcoin will not survive to that date or maybe bitcoin will survive but the price is unpredictable because its characteristic of not being stable and that's the one reason why bitcoin is unique. So while you're still alive just don't be outdated of the news related to bitcoin. So you can control your coins anytime.