While it's ironic, self-custody is hard. If thieves were determined to break into my house, could they do it? Probably. Would my safe be enough to keep them at bay? I really don't know.
the question is do they know crypto?
maybe the thieves don't know before seeing the bitcoin sticker sticking front cupboard, and after seeing the bitcoin sticker they tried to find the private key in your safe. What I mean is as long as they don't know what you're keeping, you will okay.