The key difference is that there's an entire network that needs securing with a minimum cost to secure. By contrast you can secure your own gold for free by bur

The key difference is that there's an entire network that needs securing with a minimum cost to secure. By contrast you can secure your own gold for free by burying it in the ground if you so wish, and other people not securing it properly didn't prevent people from transacting with gold throughout history. The gold storage cost is the equivalent of buying a cold wallet and keeping it in a safe place (crypto has that as well, but it's not a problem). The 'mining' is the equivalent of subsidising a banking system