No, general OS shouldn't depend on Python. Even if Ubuntu.

The several packages depend on Python 3.8 and declare Breaks for Python 3.9 or later. This is very annoying. So, we're here for alter those package to be not depending (effectively).

Example:

• focal:obs-studio - It seems that the Python installation is optional, but package is requiring python. Bionic doesn't have this issue.
• focal:obs-plugins - Same as obs-studio. Bionic doesn't have this issue.
• ansible - written in Python (wikidata). You must avoid it.
• ubuntu-minimal - It looks like necessary package, but it's not. It's just a meta-package.
• apturl - use https://github.com/AntiUbuntuPython/apt-url-glue instead.
• apport - It is kernel-level crush-handler. Can removed safely.
• unattended-upgrades - It is periodic apt upgrade handler. Can removed safely (if your machines are not sensitive).
• mate-menu / mate-tweak / mate-dock-applet - no solutions―yet.
• lsb-release - use https://github.com/AntiUbuntuPython/lsb-release-rs instead.
• netplan.io - ipupdown can be used
• cloud-init - This package depends both netplan.io and python3. You must avoid this.
• ubuntu-drivers-common - This package depends python3-apt, python3-xkit, python3-click.
  • NOTE: Perhaps you should not remove this package. This is depended from nvidia-common, ubuntu-desktop, mate-desktop, and so on.
• software-properties-common - This provides add-apt-repository(1), but same effect can be archived by editing sourcefile manually.

Now you can sudo apt remove python3! Then reboot. If all thihgs are working fine, then cograts. You've well done!