Log out after inactivity option is grayed out

I am attempting set my Mac to NOT log out when not in use.

Mac Studio Monterey 12.6

I have followed this support guide Set your Mac to log out when not in use - Apple Support

however the option to turn off the automatic log out or extend the time is grayed out.

This is a particularly annoying issue because it is not consistent what the Mac deems as inactivity. For example when I have a large volume of video files syncing in the background via Dropbox, the Mac will log out after 30 mins which will then stop file syncing.

It will also try to force close applications and projects that I do not necessarily want closed due to "inactivity" Simply going to a lock screen and putting the computer to sleep is all I need.

This is essentially no different than an automatic shutdown after 30 mins of inactivity due to all applications and background processes being killed.