It depends on what the person had in mind for their investments. Some people have a specific price they're waiting for to take profit, so when that time comes, I see nothing wrong in taking profit at that point. I don't believe Bitcoin is ever going to have a peak. I mean a price that it can't get past, not in the next 50 years at least, in my opinion, so when will be the right time to take profit? The right time for another person may not be the right time for me because we have different things in mind when we invest.

As long as it was a calculated and thought-out time to take profit, I don't see a problem. The problem is when they take profit out of FUD or out of panic, and even at that, I don't entirely blame them. You can't be certain which way bitcoin will go, and if it goes down, you can't tell how long before it gets to another ATH again.