The reality is that they would not have been able to hold for so long even if they bought 10 years ago. Very few have the patience to wait till 100x or more. Most of the investors will be sold at the idea of 2x or 3x itself. Some of the people that were able to hold for so long were those who had invested and then completely forgot about it. There is one more category of people who had complete trust on BTC and thus they stick with it for years.
People will usually choose to sell their Bitcoin while earning x2, x3 profit rather than to hold 10 years without any assurance that it can be x10, x100. Of course, I'll do the same. In fact, if I can make a profit x2 or x3 in every bullish, I can probably make more than x10 less than 10 years.
10 years is too tough for me to hold, I can't assure that. Maybe this is suitable for rich people who don't mind their investment but for us who valued every pump, I don't think we are not get tempted to sell our Bitcoin.