Of course, when you die, there are often lots of other problems for the survivors to take care of. When my mother had to be put in a nursing home a few years back, we had an estate sale ran by a little old lady who, frankly, did not do the best job for us. Then we ran another estate sale of our own because we felt we needed to get rid of all the crap that hadn't sold before. Then we went and gave things to people, donated things to the Salvation Army thrift store until they told us they were full up, and so on.
Now, if we'd had the time and patience, we could probably have eBayed or otherwise disposed of these things to people who would be excited by them. My mother had some of her mother's old phonograph records; they had Thomas Edison's picture on the label, and dated from almost a hundred years ago. They went to the thrift store. My Hot Wheels collection went for a few dollars for the whole thing (the auction lady apologized for that, but the apology did no good after somebody took a box of assorted plastic junk for $5 with all the 1960s Hot Wheels cars, etc. in the bottom). I don't go look up how much they could have been sold for if I'd had the time and energy to eBay them to collectors, because I don't want to know.
There are lots of examples like this of things that could have been valuable if we'd had time and storage space. But in the end, I have to say maybe it's better to get it over with and get on with life. Some other soul will have the experience of a find of a lifetime, and I wish them joy of it. I have enough problems of my own.
My grandmother's very old and ill, and often mentally confused. Ten years ago she had a huge house filled with memories -- photos, furniture, things of her children. Then she had to move to a smaller house, then an apartment, then assisted living, and now she's in a nursing home, where she space for virtually no personal items. My mother has a few things (which she doesn't want, but can't get rid of), but mostly, it's all gone, and grandma isn't even dead yet. I don't know whether it's better or worse that she doesn't know or care anymore. Even when she moved out of the house, the things she chose to keep and get rid of made no sense -- her mind was going, and value -- monetary or sentimental -- were already of lessening consequence.
Yes, I think it's better that she doesn't know. She will find peace of a sort as she declines, just as my mother has. I empathize and hope your family deals with this as best as it can.