Because a flippening during a major crash won't confuse new entrants, the narrative is easy to understand, "bitcoin crashed 80%, then it rose again", they won't notice the flippening even happened. Stocks often crash and then recover, so it's not unusual, but stocks don't experience flippening
Don't forget, crypto total user base is tiny, and on the next bull millions of new users will enter the market. Previously I could not see flippening as likely as during a bull market it has to be done in the open - 'one bitcoin dropped from 20k to 1k, and another bitcoin went from 1k to 20k ... wtf.... ' Only those deeply embedded in crypto would understand what the fuck was going on, so major turn off.
What can happen now is both bitcoins get flushed down the toilet, then 'the bitcoin' rises up again ... simple, easy to understand for the millions of noobies entering the market on the next leg up.
Edit, a flippening at 20k USD would have crashed the market, we all knew that, and so many would resist it even if they prefer BCH, but now ... market is already trashed, so might as well flip