what if we reverse the situation. John buys Bitcoin at a price of $ 4k and then the price of Bitcoin goes up to $ 18k, how much bitcoin that John produces and how much bitcoin John is lost, 1 bitcoin is still 1 bitcoin..  if John does not panic and stay calm with the decline in the price of Bitcoin then John will not experience a loss, believe the price of Bitcoin will not forever fall, there will be a time when the price of Bitcoin goes up again.

if I were John then I would remain calm with the bear market and stay focused with my bet. but this is the problem, everyone's way of dealing with problems is very different.