Four amigos are known. But the big question is will all four of them be relevant at next economic collapse or only sold and silver. That is a billion dollar question. Are Bitcoin and Monero ready for central banks to see them as one of the four amigos.
I think that every one of the assets will sink deep to lows people thought to not be possible anymore due to the fundamental growth and whatnot.
Fiat will always be a safe haven, especially in times where fiat is the only form of money that gets the bills paid, and in times where people lose jobs, sell everything to pay their bills, fiat will most likely be the only in-demand asset. People usually only focus on the USD, but there are more large currencies that are able to function as safety net.
I sincerely hope that I am wrong on that and Bitcoin will do well, but given its speculative nature, it's very hard to believe.