Gold can't be sold (easy), unless you trust the bank to hold it, but then, if the bank fails you might not get your gold or your money back.

Also, gold won't help at all in case of a crash. What you'll need is food and gold value is too big to buy food. Silver might work, but it has taxes unlike gold.

Gold can absolutely help in a crash. While it's more correlated to equities than bonds or cash, its better to be in equities and gold than pure equities in an equities crash during a period of high inflation.