I actually know someone this happened to — a guy I met a while back died unexpectedly in an accident. He had a cold wallet with a decent chunk of BTC, and to this day, his wife still hasn’t been able to recover any of it. He didn’t use any kind of inheritance system or trusted setup. It’s just... gone.
No matter how much assets a person has, it is worthless if he cannot pass it on to his heirs before his death. There are many who may have given their wallet keys to someone, but I think it is important to ensure that they are not only given the keys but also given the necessary education in using Bitcoin. People can die at any time, but if these tasks are not completed in advance, any accident can happen. So an investor should first complete these tasks while holding Bitcoin, otherwise the person may lose his wealth forever.