Some Linux systems like “Arsch”-Linux dilligaf you and install the upgrade to Blender 3.0 anyway, even if you explicitly marked it to ignore. They even trick you and simply reset your choice silently every time you start the package manager (Manjaro). Thats not what an armory user wants. We need 2.93.6 as default Blender.
As downgrading leaves you sometimes with a broken Blender installation i recommend to create a soft link to Blender 2.93.6 in the directory where the system installed the 3.0 executable:
Let the system upgrade to Blender 3.
Download 2.93.6 manually. Unpack it somewhere.
Rename blender in /usr/bin/ to blender3
Execute following command in terminal
sudo ln -s /path to Blender 2.93.6/ /usr/bin/
Now clicking on a blend starts 2.93.6 again. To start Blender 3.0
start terminal and type blender3.