Hide system tray and/or lockdown access to network config and defender

If operating in the mode with the Windows desktop available, it appears the user can access the apps in the system tray including Windows Defender. This gives them the ability to change any of the security settings on the system. They can also edit power settings.

Is there a way to prevent this?

OK, Figured out that you can disable the Windows Defender icon at least:

Task Manager > Startup > Windows Defender Notification Icon > Disable

That helps a lot, but it would be nice to get rid of the rest of the system tray as well.