Is only an immature trader that sees bull times as the only or appropriate time to make profit in trade. A good trader makes profit even in bear market. He/she milks the market at anytime he is convinced for a trade.
I agree with you in the essential, but you have to keep in mind that the nature of the crypto market is very different from that of traditional markets, so much has been insisted that the ideal strategy in the specific case of bitcoin is to buy and "hodl" "as a long-term investment. And that is why a bear market does not serve at all to fully comply with the primordial "commandment" of a bitcoin holder.