That article is one of the great reason to consider in future too. Exchanges hodl bitcoin, not just hold. Why? Do you think they are crazy? I highly doubt that because crazy persons never run successful businesses and especially those ones which includes worldwide users.
There is no need of panic selling but I don't say to hodl if forever, bitcoin is currency and payment method which has to be used in order to adopt it in a lot of services, well it's whole different subject but to sum up, bitcoin will reach it's all time high anyway, so it worths to save your bitcoins and not sell now when price is really low.