Remember that bitcoin is a very high risk investment. It's like you'll never know if you still have the original amount from couple of days ago or so. And if you invested your entire life savings, you can't sleep very well in that case. While if you have the gold, you're not that scared to lose it the next day. You are still confident that you have your gold investments. But, it's up to an individual where he wants to risk his money. It's his own money anyway.