Possessing a library that's not a mobile library is an extremely classist thing
Classist is a strong word. I'd say its more for people with permanent homes, which didnt use to be a point of contention between social classes, but now is, and not to the fault of the home owners themselves (since the government needs only to build affordable housing, or encourage housing associations to end this crisis).
There is something to be said for supporting creators by buying physical goods mostly while they're alive.
I agree, which is why I donate directly to the creator. I download the DRM-free content, and then seek out the authors homepage.
Middlemen are important curators in our lives.
In the context of regulators, preventing anti-competitive practices from taking place, I agree. In the context of large publishers, retailers, and market vendors who demand that creators use them or face obscurity? No, I don't believe they add anything.
Physical items have a provenance to them while files just have metadata.
Not all provenance is good though, and at least files can error-correct themselves to some degree