There's still the guilt when you have to tell the movers that this big stack of boxes is filled with heavy books.
I get rid of any book that can be found used for under a couple bucks or so used online, unless I am actively reading it or need it for something. I can always get it again later when I feel like reading it, just bookmark a link to the place it's sold.
Why guilt? No reason to feel guilty for anything.
I collect old books and buy anything that I can find pre-1950. Last time we moved I had 2000+ books in ~15kg boxes. No guild or shame about it. I love my books.
I get rid of any book that can be found used for under a couple bucks or so used online, unless I am actively reading it or need it for something. I can always get it again later when I feel like reading it, just bookmark a link to the place it's sold.