When you use quantum computing to store your bitcoins safely, it gives you privacy but your next generation will not be able to access it in any way. Quantum computing is not necessary to store bitcoins safely. You can hold your bitcoins in any wallet and it must be non-custodial. And if you have a very large amount of bitcoins, you can use a hot wallet or use a hardware wallet that will give you complete security. You will also get better security if you use an electrum wallet. Bitcoin is now a very simple investment asset so there is no need to think about it in a complex way.