Part existence probability changes every couple of months, probably not enough time for you to be able to make good estimates.
LEGO tends to get hoarded, resold or donated, not thrown away. I believe I have more than 99% of all the LEGO I or my parents ever bought, going back to 1976 or 7.
Tell that to my Mother. She threw away all of our 1970s and 1980s legos, transformers, Star Wars, He-man, etc. toys after we left home. Didn’t even donate them - straight to the landfill.
I was surprised by how complete some sets of mine where when they came over. I don't doubt the 99%, although in my case they are not mine any longer as such, but my five year old son's.
Lego stashes do indeed get hoarded for a generation at a time; a lot of it is kept as valuable for the next generation (lucky bastards).
> LEGO tends to get hoarded, resold or donated, not thrown away.
I doubt this. Outside Lego enthusiasts, most people see it as a children's toy which is probably disgustingly covered in saliva and in no fit state for anyone else to touch. It's one of the first things to go into the trash when more space is needed in the attic.
You can put them into a pillowcase and wash in a washing machine.
Given how expensive Legos are many people will gladly pick them up from your place, especially if you live in a city. You can look up Buy Nothing and similar groups in your area on FB.
LEGO tends to get hoarded, resold or donated, not thrown away. I believe I have more than 99% of all the LEGO I or my parents ever bought, going back to 1976 or 7.