It's the fear that cause people to panic so it's same thing, I don't think someone that's held bitcoin for a long time should have any reason to panic cause from experience they should've already known that their must be an occurrence of volatility in bitcoin investment, meaning that the price would go down and also go back up due to demand and supply, it's people that's not held for long or who recently started holding that would panic in times like this.

 That's why every true Bitcoin investor shouldn't just know about it but put it to practice and hold for long, atleast for a full circle and more so you'll have the practical experience of how it operates and see the drop in price as an advantage to buy more coin and hold instead of panicking, it takes courage to be an investor in Bitcoin, the road is not always smooth meaning that their would be some hindrance like negative news that would affect the market and trigger some panic but true investors won't be discouraged, they'll be patient, take it to their advantage and keep hoping for a more better future.