Bitcoin price movements are no secret, so it's easy to look at the charts and see for yourself. Bitcoin drops in value dramatically regularly (although that also depends on what you consider a dramatic drop). Sometimes it can recover quite fast, but if it's the bear market coming, it might take several years (around 3 years, to be more exact) for Bitcoin to fully recover. That's just how it works, which is why patience is key with Bitcoin. If you're not okay with your investment being 60% down for a couple of years, Bitcoin just might not be for you.
Everything about bitcoin is transparent and everything can be clearly understood so there is no need to think anything is secret a true word was said there, the only thing you need is to understand the market and the chart then you have less worries and you will see everything in the chart the period there was an increase and the time the market was down, it is all shown in the chart and it's very easy to read just that people are lazy and they don't want to stress there self to much in reading does chart.
And for now how the market drops does not matter that much and when you already have knowledge about bitcoin I don't see the reason why anyone need to panic against the dramatic fall that is even if there is one because understanding the dramatic fall is what I don't even understand and you can predict the future of bitcoin sometimes, because the price might drop and the next thing might be another increase.
And patience is just the key thing as you said, there is no way you want to do a long time investment and you won't have patience is not even possible, so anyone one your tell about any long time investment should be ready to hold on for a long time.