Yes I agree but you should not forget to respect others opinion. We don't know what their reasons of selling their bitcoin because as far as I know there are different kinds of techniques and style by dealing this crypto market downfall. Maybe they are in great needs that's why they sell it.
Traders usually sold their bitcoin because its their job and they have to commit on their goal. Its not an stupid thing when you sold your bitcoin unless you sold it during the bear market and you incur big loss for that deision, so basically this can be a stupid thing youve ever done.