greedy is not a good trait, even though it is greedy when someone else is afraid. I think it's more appropriate if we replace the word "greedy" to "spirit".
'we have to keep on encouraging when other people are afraid', I think these words are more constructive and better.
when other people are afraid of the current market situation, we must be more enthusiastic, even have to be able to buy coins that have the potential to have a good future, so that we will benefit if one day the market prices recover.