rpm -q appstream-data gives the same output as in your example. I have killed gnome-software before running
pkcon. I even tried that multiple times when there were some updates to
gnome-software package - after updating the system, I restarted it, killed gnome-software and run
pkcon. The issue did not resolve. The only thing I got was that a progress bar showed for a few seconds when I opened gnome-software, but then it went back to “No Application Data Found” state.
Hrm, that sounds like something else then. Please open a new topic and we’ll debug it there (since this one seems to be solved by the workaround).
The new topic is here: Gnome Software keeps showing "No Application Data Found". Thanks