We will all go Richard , some collectors wont let go of the coins though and literally take them to the grave which is obviously there own choice.
Maybe another option for the people who wont sell is to make an agreement with someone in the industry who they know and trust to sell the coins when they have gone and make the people who inherit them aware that they will help and hopefully maximise the money. Even if its just to put them all in one auction they will atleast get someone acting in there interests rather than just passing the box to an auctioneer.
If the person in the industry pass away first , they can always find someone else 😃