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.
It becomes a problem if you do not tell your closest family how to access your wallet. The effort to store Bitcoin for a long time will be in vain without being enjoyed by our heirs.
It’s never a problem if you end up dead. In fact, you might have no knowledge of ever owning Bitcoin but, it will sure serve its use some place else and that is; it would add to the uncirculated Bitcoin out there, making Bitcoin the more scares and valued by those who own and have access to them.
If your unfortunate event isn’t death but some temporal disability that renders your body and ability to function impossible with your Bitcoin hodlings being a source of funds to your revival, then we could have a problem but, family and friends out to know how to find a way and resolve all that later when you regain consciousness.