Here's my explanation as an ex fund manager:

Gold is the Schelling point flight-to-safety, anti-inflation good. Silver has similar qualities, and might as well be the same thing economically, but it isn't. You're more likely to have heard of gold bugs than silver bugs.

When it comes to a massive market panic like this, people think about what other people think about. Well, they always do that, but when there's a panic people have certain safe haven assets that everyone "agrees" are more likely to be safe than others.

Bonds are another one, though of course there you have historically had massive government intervention, making it a little less unintuitive why people should buy them.