dumb people sell
smart people buy
choose your side !
People that sell their coins are not "Dumb". They probably sold their coins for their own reasoning.
Everybody has own perspective in life so if he sell it or not is none of our business. Maybe some really needs some money badly while some chooses to hold because of believing that soon it'll recovers. Some sees crashing a negative outlook in the market like thinking it's dead end but some sees crashing a good way to buy more and be wealthy in time as so let's do what's think it's right and respect others decision.