We should trust our experience in trading even though the situations got worst, and I don't think panic selling is the solution. What will happen to your future profit if you sell it all due to you're panicked? That's why we should stay stronger and keep the faith burning so we could stand against negative speculators.
How could we trust our trading experience while we seen our coins in danger of being dead? You can't motivate a hopeless person mate while you don't know exactly what to do. I know you're just too positive enough to say keep the faith, but I don't know you can do it in real situations.
Maybe what the OP is suggesting is that we should trust the system and even though that our portfolio is down, we can't be that hopeless because we all know that it can bounce back anytime soon. If you are a experience trading, you wouldn't panic that easy and used our common sense.
We could not prevent the speculator to say their negative ideas, because we have our free will of giving opinions based on how we analyze the trend of trading price of each and every coins in the crypto market.
Of course everyone is entitled to their opinion, but its up to us to whether believe it or just ignore those. Specially pessimism which has became the norm of the forum lately specially in this bearish trend. We should rely on our own decision by doing our homework and validating everyone's opinion regarding the price movement.