The person who sold Bitcoin at a cheap price without holding it will regret it for the rest of his life. The longer he passes, the more his regret will increase. In reality, when someone buys Bitcoin, the importance of holding it is not well understood, but it becomes easier to understand with time. At some point, the investor realizes how much he has made a mistake in his life.
That is why it is better to take advantage of the opportunity when it comes. Moreover, every investment has risks, so if you want to get something good, you must invest, but you should also consider whether you have the ability. If you do not have the ability to hold it for the long term, then there is no point in buying that asset.
You mean a person like Lazlo who sold a large portion of his BTC for two pizzas? Up to this date, he doesn't regret his decision. You see, no one knows whenever BTC will keep going up in price or lose its value overnight. What's holding it together are the people supporting it. But what if governments worldwide decide to unilaterally "ban" Bitcoin or make it "illegal" for mainstream use? Then, prices will surely go all the way down the drain in an instant.
Some people are able to "hodl" their Bitcoin for long, while others can't due to life necessities and stuff. It all depends on your current financial situation. A price of $63k - $64k may be considered "too early" if you believe BTC will reach $1m in the future. Or it could be already "too late", if market prices don't go any higher. I'd just forget about market prices and carry on with life as usual.