Earlier quoted context omitted.
It's not especially inconvenient to own several thousand books Until you find yourself having to move.
I have thousands of books and would love to get rid of them. I would need a future-proof platform that allows annotations, and that lets me migrate between devices (so I can keep my books for at least my lifetime). I guess I would also need a convenient book scanner, for those books that are no longer in print.
I recently scanned a bunch of books using gscan2pdf; it makes it relatively easy, and integrates some decent utilities like Tesseract for OCR. (Some fiddling with controls meant that I could start playing a movie and mechanically flip pages and punch the scan button.)
Relatively high-resolution scans like 3-500 DPI mean you can get big PDFs (~200MB for a big anthology was normal), but this isn't much of a concern to me: I can clean them up later if I really need space, and in an era where 1.5tb is 100$, 200MB is nothing (1 or 2 cents of space?).