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.
I agree with you at some points.
There are many people who are regretting of not knowing it sooner. However, if they were to know it a little bit early, it still isn't guaranteed that they will trust bitcoin so much that they will hold everything they own until they can, most especially knowing that bitcoin has a little value before. Only a few people actually held all of their coins up until this date without selling even a portion of what they had initially invested in it. Because before, only a small population ever really believed in bitcoin's potential. I remember a story of a man who just used his bitcoins just to buy some pizza because who would have anticipated that a coin will have so much value in the future, right? Only a few and those few people are smart and lucky ones.
But still, those who managed to invest before bitcoin really peaked and boomed are still considered lucky even though they weren't able to buy it during the time it has little to no value yet. I suppose they still made a large profit and maybe some even became millionaires if they managed to hold until the ATH. It still isn't too late to invest after all. Just make sure to know when is the best time to enter the market and when to take profits. With the supply and demand of bitcoin, who knows how much it will cost in the future. Only time would tell and I hope those people who opt to trust bitcoin will harvest the fruit of their patience big time during that time. Right now, everyone has been given the chance to invest in it before it skyrockets again, the choice is still yours. DYOR.