It's an interesting idea
I've already given BTC as a paper wallet, I just printed it out, put BTC in the address and gave it as a gift
But to last that long I can only think of one idea, something like the cryptosteel, some metal object where you record the seed and give it to the person.
In a few years any hardware can fail, with or without batteries
That is what worries me the most. For such a long period, it is easily possible that the company that produces the hardware ceases to exist and therefore ceases to provide support. Maybe I should save to offline drive all the documentation and current software that would reduce the risk, but not completely.
In this case, the most important thing is to choose a wallet that have the standard BIP39 for example
Even if they stop to produce and sell hardwallet, you can continue using in another wallets, and in extreme situations, you just need your seed to put in another wallet
The important thing here is the seed / private key