I don't know how it would be implemented but it is quite possible that private wallet insurance might emerge.
I'll believe it as soon as someone presents a pricing scheme for it that is both affordable and actuarially sound.
Insurance isn't magic pixie dust - doing it correctly means having the ability to accurately calculate the risk of insured losses, and for that risk to be low enough that customers are willing to pay for it (either directly via premiums, or indirectly via opportunity cost).
I agree. By "how it would be implemented" I was thinking that it will necessarily be bound to the wallet owner following some provable steps of safe keeping. After all, one of the events that you would want insured is the theft of btc by sweeping into another wallet. So there would need to be a way to show that the policy holder wasn't just stealing their own money and then putting in a claim.