Different persons have different ideology of holding Bitcoin for long time so the essence of holding bitcoin from my own perspective of life is that you have to understand the procedures of investment because holding Bitcoin is like having a target of multiplying what you have because any crypto investor have plans and the plan of holding bitcoin is to make a profit in future so the essence of holding bitcoin for long time is to make a profit in nearest future so that is why many persons indulge in Bitcoin holding and also bitcoin investment for long term
Holding is not necessary but rather an option for everyone as it depends on their preferences and investment plans that is my understanding. But yes, it was best to get this plan especially if we don't have the urge to sell our bitcoin. Maybe holding for 4-5 years is quite enough, we're making good profit from that long when sell them during bull season.
The common reason why some are not able to hold is because of the lack of understanding which drives their minds to worry and feel uncomfortable especially when seeing a declining scenario. The volatility of the market makes someone feel uneasy, they always think of negativity rather than thinking positively. I think convincing people to keep calm is not effective, still their minds manipulate their actions.