(Googling I just seemed to get spine thickness and format sizes but not an average of actual printed thickness )
It has 21 books in 28 inches.
1.34 inches per book.
I get 279 linear feet for 2,500 books.
Checking Amazon, Walmart, the book cases they sell seem to be 5-6 tier with 24 inch width. (Though checking my non built in ones, all of the ones I own are around 4 feet).
Using the Amazon average, you’d need 24 book cases to fit all of them… which does seem like a lot. Wonderful but a lot.
I do have a kindle, and I love it. But something about physical books is great.
I have 5 built in book cases of various sizes, and 6, four feet Wide book cases that are 5 or 6 tiers… and yet I still have bins and bins of books in my attic.
Initially I had thought “that’s manageable” but upon some self reflection you make an excellent point.
My ideal library is a hybrid: physical for art books, kid's books, reference books, large format or special edition, signed copies or sentimental treasures, etc., and digital for everything else. An iPad as a digital card catalog for the entire collection and a couple of Kindles for actual reading. (Impossible to browse on a Kindle ...)