This is focused on the ledger because its the wallet I have
Sure, but it might not be the wallet
they have. If this is 10 years in the future, who's to say that the Ledger Nano S is still being built or sold? Highly unlikely. And even if they can manage to get their hands on an old one, will it still be compatible? And if it is, the firmware on the device and the Ledger Live software will both almost certainly have changed significant, and render some of your instructions wrong. You've written a good set of instructions for how things stand at the moment, but one update from Ledger would be enough to render them incorrect or incomplete.
Now, if something was to change as I've described above, it might be enough to trip up a complete newbie or someone with low technical knowledge, but someone like me or you who understands what a mnemonic phrase is, what a passphrase is, and how they relate, would still be able to figure it out without too much difficulty. With that in mind, I think you should absolutely pass on your instructions, but it would be wise to also include either an explanation you've written, or a link to where they could find an explanation, as to some basic bitcoin terminology and wallet guides. That way, if your method is no longer valid, they will at least have a starting point to educate themselves as to how to recover your coins using a different method.