that still remains an isolated incident whereas there have been other cases of other markets crashing while bitcoin not giving a shit about any of it all. nowadays it is being exaggerated in the media for FUD purposes.
It's like ETFbitcoin said - Bitcoin is not affect by markets, it's affected by large events. So far the coronavirus outbreak is the only event large enough to shake Bitcoin. But there can be and will be more in the future.
additionally if you check bitcoin behavior with other markets you can clearly see that the drop that bitcoin had was a normal size drop that is also very common in bitcoin world. meanwhile the drops that other markets had were catastrophic by their standard and extremely rare. adding the fact that bitcoin recovered as soon as the panic sell (because other markets were dumping and FUD was at its peak) ended you can see bitcoin outperformed everything else.
50% drop in a day is not common, it usually only happened when the big bubbles were popped, and while it was partially a correction from the small rally that happened at that time, the drop was still too sharp and too deep to be brushed off as a normal case of volatility. And Bitcoin didn't really outperform everything else, it's still on the level it was before the crisis, while gold is 20% up since the beginning of the year.
Also, this year's halvening might have contributed to the quick recovery, and you can't rely on that every time.
