The memory may still be intact, though I certainly wouldn't expect it to be by then. I think flash storage needs spurts of electricity every now and then to maintain its stability. The above link cites 30 years but also adds that's with occasional use. There's no type of battery.

Your bigger problem will be software and firmware. It's doubtful Ledger will be an ongoing concern and whatever code they came out with will either be long since compromised or unusable on modern machinery and that's before we consider whether there'll be any type of USB connection by that point in time.

I regard the Ledger as disposable element. The seed is the permanent one.