We live in a four unit building and one of the units just went on the market. The former tenants cleared out everything for their open house and just brought in some minimal, modern "staging" furniture. It was astonishing to see essentially the same apartment layout but with none of the stuff — a kind of bizarre alternate reality. It prompted our new year's resolution: we will get rid of (at least) 5 things a day for a year. So far so good, and we've cleared off and removed an entire set of shelves.
You really have thousands of things you can get rid of? My house is a mess because my wife won't stop buying things for the kids but even so, I'm sure there's not 365x5 things in here I could get rid of, unless I could every sticker and crayon separately.
The goal is just 5 * 365 = 1825 things. I'd wager that most of us over the age of 30 have/had at least that many things we could get rid of before our first experience in purging.