How do you protect #bitcoin keys to the point of being able to let every day people use it day to day?

I mean, data is much easier to lose than hard cash, and the attack surface is global.

I don't see how it could ever be practical to be custodians of our own wealth without it being a physical object.

Sure someone could break into a vault and steal gold, but it's pretty hard to lose a stack of bullian compared to security keys. And a lot harder to make an off by one error that loses it all.