As for setting stop loss, that's really the purpose of it.
That's going to minimize the potential losses that you'll get instead of no stopping as the market plunges so it's still a good thing that has happened to you.
But most traders won't use that strategy because they thought they know the market well.
Who would have thought that LUNA will crash this badly?
Aside from few Youtubers who predicted about this Luna catastrophe, a lot of holders were actually hoping to gain from this investment.
But I do agree with the use of stop-loss strategy, it may be your savior in some of your trades.