There will always be a risk in any investment you make. The time you bought Bitcoin or you hold your Bitcoin is considered as an investment already and has a risk because the price is unstable and price might drop or goes up. We can't compute how much is the risk but i am only sure that there is always a risk everytime you are holding Bitcoin or any crypto currency.
I agree with you crypto is quite unstable and that nature though allows us to trade more frequently that we would imagine but that also enables less trust in the asset as we are not sure if we sell some gold and buy bitcoins will the price be same or higher in next 10 years.
I mean, I am not against bitcoins but really if you are holding large numbers and the price is wining like fun, it makes anyone just sell them and play safe unless the guy is a risk taker with enough bankroll to manage in case of loss.