As a fellow old fart, I understand the impulse to worry about what will be left. If the art world is at all consistant however (BIG if), your work will be worth a lot more money after you die, so leave it in good shape for whomever does your estate. If the photos you have now (printed and not printed) are not in your way, worry more about adding to the riches than you worry about getting rid of them. Take joy in creation, whether it is through printing that early morning recollection of an almost forgotten negative or in going out and shooting more! The junk in your garage (lawn mower, old clothing, books, bric-a-brac from yard sales, etc.) will be more of a difficulty and undoubtably take up more room than your photos. You speak of having had people wish to display your work. Why do you think that will end when you are no longer around to make any more?

I think the need to throw away what we have created is always with us. Good editing practices are necessary, but you should fight the urge to purge. You took those shots and made those prints because you thought they were worth having. Buyers have proven you correct over the years. Don't start second guessing them. Yes, all we do is ephemeral–– even crap, if you want to push it–– but I believe that is no reason to make it's short life any shorter by adding to a landfill.