Clock on main taskbar only

With a multi-monitor setup, it would be nice to be able to show the clock on the main display's taskbar only, to reduce visual noise. As far as I could see, the built-in settings only allow showing clocks on all or none of taskbars, and I couldn't find other hacks.

This request is the opposite of https://tweaker.userecho.com/en/communities/1/topics/326-add-clocks-to-additional-taskbars-win-80.