Not OP, but I do similar. I only de-spine a book if it is in poor condition (and I have a nice copy). Some of the material I scan is stapled instead of glued and I can remove the staples, scan and replace with new (not rusted!) staples to return the book to its original form.

I have books but would have 5x as many if I could not capture them digitally. (When I go to move or go through a purge, some of the books I scanned do go to a used book store.)

So I scan in part to keep my physical book-footprint smaller, but also my scans all get cleaned up and uploaded to archive.org. Mainly I scan young-adult science books from the 50's and 60's (since they were so influential and have all but disappeared except on eBay and the like).

Not OP, but: If it's something I want to work from, I get a printer to slice the spine off and rebind it with a ring binding. That way it lays flat on the desk.

You've trashed the book (and its lifespan) but some books are for using, not keeping.

Sometimes? But for scanning I can use a cheap worn copy as long as the pages are clean.

Most books I would rather have a digital copy. I had four or five book cases full of stuff and it makes moving difficult.

I originally started scanning 20 years ago when it was more difficult to find PDFs of basically whatever you want. Now it is only random old books I find at the used shop or online for cheap and somehow cannot get from archive.org or elsewhere.