Both: installing apps outside of their respective stores is an adventure in terminal instead of a GUI double-click. Secure boot issues. Constant prompt for password instead of a simple PIN or other form of identity verification.
Well that is actually not true. What do you want to install? Of course if you are a power user and want some special script for whatever reason yeah I can see you being forced to use the terminal, other than that there's often a DEB you can install via GUI with double klick, there are flatpaks you can install via GUI and double click and also AppImages. You can come pretty damn far with that to be honest.
I use Debian Stable as my daily driver. No issues with steam. No issues with old packages, everything just works and is, I'm not sure why I'm shocked at this, kinda stable.
You should look into QubesOS if you are concerned about your security.
From your selection, I'd recommend Debian Stable.
As others have pointed out, Kali or the likes are the least secure operating systems, they are not designed to be secure, they are designed to be booted in a temporary environment and then used for penetration testing purposes.
Megaloblatta longipennis
I'll save everyone a click