It has been demonstrated that:

1) gold can be stolen due to mistakes

2) bitcoin can be stolen due to mistakes

but this does not mean that it is impossible to avoid having either stolen.

I agree that long term storage of both of these can be done very securely, but the risk for both is when trading or using them. Additionally, Bitcoin does require a lot of worry about security - how many people do you think have airgapped wallets?

Aren't the facts that you shouldn't store Bitcoin at exchanges, should use an airgapped storage mechanism, and are otherwise out of luck if your computer is compromised, enough to demonstrate that you also have to worry a lot about the security of Bitcoin transactions? Your stack of gold ingots won't vanish if you take one from the pile in your safe, but your Bitcoins can if you don't take stringent precautions.

If you view a Bitcoin transaction as only what happens on the blockchain, you're missing the context of where it occurs - which gives both gold and Bitcoin risk.

Good point, the minimum security of Bitcoin is that of gold; i.e. a safe guarded by people with weapons.

But since Bitcoin is digital, its maximum security is far, far higher. Your private keys can be encrypted and safely stored with any desired level of redundancy. Paper wallets are a big step backwards.

Also, if secret sharing is used, Bitcoins cannot be stolen unless the attacker gets to k of the n involved parties.

Not really. It is much easier to lose or make illegible a piece of paper or data than it is to lose large heavy gold or to damage the gold to a degree that severely reduces its value.

OTOH, its hard to make redundant copies of a gold bar that retain the full value of the original so that if the original is damaged, nothing is lost.

Actually, you could--you could irradiate the gold to the point where decontamination would cost on the order of the worth of the gold itself.

I don't know about you, but no, I can't do that.

upvote for mentioning the evil scheming of a Bond villain in a serious conversation as a serious answer :)

No one said it was impossible to damage gold (there are easier wayd than to make it radioactive).

It's just much harder compared to doing comparable or greater value destruction to a bitcoin address, especially accidentally.