Depending on your organization, this may be enough.
This does absolutely nothing to prevent someone from doing it anyway, but it asserts authority without removing any privileges. Be sure to specify IT’s stance for non-compliance.
The easiest method for preventing unwanted installations is to disclose your organization’s policy to end users that states “Do not install major macOS upgrades unless authorized by Information Technology”. That usually means we need to be taking more than just one step. What steps can we take to prevent our end users from installing a new major macOS version? Keep in mind, end users can acquire the installer and run it in multiple ways. Not every administrator is ready to support Monterey, but sometimes our end users get ahead of us and install it themselves.
It’s an established pattern that’s been in place for a decade.
It released Mac OS X Lion (10.7) in 2011 and every year since has released a new major version.