Although he may have been "right", you can't rule out coincidence. Also, his own son doesn't think he's always right, lol - https://twitter.com/PeterSchiff/status/1303009420713111553?s=20

Having said that, I wouldn't go by everything he says when it comes to bitcoin especially considering he has vested interests and an agenda. I do however, think that bitcoin would crash along with stocks but would recover much faster. Rather than trying to time the market, it's best to be in in it long term if you believe in it. It'll probably weather the crash and then go to new heights pretty quick post that.