My experience may be relevant: 23 years ago my wife and I moved from a fairly large house near the beach in San Diego to a fairly tiny house in the mountains in Central Arizona. Getting rid of excess furniture was easy (I gave my Eames Chair and standing teak chess board to people I really liked), but I had a huge library. For many years I bought about one book a week from the San Diego Technical Bookstore. I got rid of about 60% of my physical books, so I only had two large bookshelves in my home office. After temporarily moving for work, I cut my books down to half a large book shelf, my wife using the other half.

The trick that worked for me was to just keep books that I had a strong emotional attachment to. Some books that I want to refer to I simply re-purchase as eBooks from Google or Kindle. Now half my physical books non-technical (Joseph Campbell, spiritual stuff, favorite literature).