Dave,
Fedora moved calibre to python3 much sooner than upstream did because python2 was being phased out in fedora. Unfortunately, we can't upgrade to 5.x due to some dependencies in other packages not being ready yet. ;(
Fascinating. I wonder why DeDRM is working for me then, on F33, with Python 3 as the system-wide default?
I'm running a fresh install of F33. By any chance your's is an upgrade from a prior version with python2?