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.
even with a reality as this, there is another side to this that when you consider it, it makes you think twice about letting anyone know your seed phrase. people can be really selfish including your partner and letting them know your seed phrase can even lead to them planning your death. of cause, no one ever believes that they might just die any day and that there is a need to make preparation for such uncertainty that is bound to happen as long as life is concerned but then, doing certain thing could easily send you to your early grave.
for the married that have children, that are matured and that they can trust, it is better to confide in them with at least some information regarding an aspect of your holding while you leave the risk only to your knowledge. exposing all the asset you are holding to your family just because you care about how they might fair after you have died will bring a sense of entitlement which will make them try to spend all the money out even while you are still alive. the highest i can do is to divide my holding into two portion, let them know of a part while i keep the rest only to myself.