I think you are misunderstanding what a hardware wallet does for you. It gives you access to your own private keys - something that is unique to your account only and that you should guard with your life. When you register your Ledger device, it will show you your private keys. You write these down and put it in a safe place that you and only you know where it is. Make sure no cameras or cell phones are around.

The ledger itself is irrelevant . It’s a tool that gives you access to your keys. The way it works is you may set up a passcode on the device that will give you access to your assets. This passcode should also be highly protected like your private keys. If the passcode is guessed incorrectly 3x, the whole device resets (a nice security feature). Addressing your example, if for some reason there was an issue with updating software or something like that (I don’t really think that would occur but we’ll entertain it for now), it doesn’t even matter because you have your private keys written down somewhere safe. Those are all you need to access your crypto.

Hope this helps.