I believe that the reason is the lack of appstream metadata in Kali repositories:
https://www.freedesktop.org/wiki/Distributions/AppStream/
http://dep.debian.net/deps/dep11/

Debian repositories have this. But we are using reprepro to manage the repository and it doesn't offer this feature currently.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=824521

Hello friends,

Upping this one with a KDE Discover screenshot demonstrating the same issue.

I added comments in both Debian bug discussion and aptly's issue on GH (https://github.com/aptly-dev/aptly/pull/473) in the hope it will revive will to improve the situation.

@rhertzog like said there, don't know what the amount would be, but again I'd gladly help funding the resolution of this here and anywhere upstream. Kali is AFAIC the very best Debian based KDE workstation OS and this one is a pain for UX.

Thanks for all the amazing work folks. Have a beautiful WE :)

PS: Can't Kali infrastructure make use of appstream-generator on its own without depending on repository management software ? As I understand it, it looks like KDE Neon is doing so with Aptly: https://community.kde.org/Neon/Appstream

Screenshot_20220709_182757.png (91,285 bytes)   

Screenshot_20220709_182757.png (91,285 bytes)   

At some point the appstream files must be recorded in the "Release" file managed by reprepro. There might be ways to script a change to this file with some hook but it's non trivial (and nobody has done it yet on the Kali side).