A personal library is effed, tho, because some flash fails if the blocks are not cycled. E.g., multi-level cell flash requires at least a refresh, of I think, 36 months (don't quote me)? Basically: the blocks need to be copied and erased periodically (this isn't wear leveling it is something else and I'm now out of my depth). Probably not an issue with lower density, thicker oxide single-bit-cell flash.
I still keep my favorite books in paper format. All of my digital books are loans from my library. If I really like it, I buy a physical copy.
As for libraries and DRM, well, that's a horse of a different color.