Those who bought bitcoin earlier at a cheaper price, of course, made a profit and perhaps even now with a profit, there are those who bought bitcoin when it was close to its ATH and now they are at a loss. If the financial situation allows, then just need to hold and the situation will be corrected, can also buy more now, to average the price. But the most important thing in this situation is not to sell at a loss, because when bitcoin rises in price again, the situation cannot be corrected...
According to some analysts, the current decline in bitcoin is normal things and need to be like this, because bear market actually good for the long-term price of bitcoin itself in the future. I also believe in that. Because, no business is 100% profitable, buying stocks and gold which is said to be lower risk, also experiences a bear market. Of course this is only a predictions, but the cycle and history maybe have similar pattern. Just wait and see, bitcoin rises again.