I believe many newbies in the topic want trading to be the same as a “regular-paying” job. It’s a mistake in my opinion, and that mistake will cause you to be inefficient with your capital, because it will make you sell early and miss plenty of profits.
You are right for bitcoin market and for most of the altcoin markets, booking profits time to time might lead them achieving what they really want to. I agree that trading nowhere near to regular job but for the skilled traders it will pay more than a regular job. So, regularly booking profits may be a right approach even with bitcoin markets compared to long term holding when you plan up buying back when bottom reached.
Other people they see are only showing off their gains, not their losses. We don't know how big the loss is compared to the gain.
Similarly traders do hide about their big profits from trading for no reason and might give out only clues. So, both big achievements and big frustrations are not showing off which is the reason why we always have delusional belief on trading which sometimes leads traders to go greedy.