Any way to lower the UI scaling below 100% in Windows 11 23H2?

That means below 100% is not supported.

This is possible if you use the Custom Resolution Utility to add a higher resolution to your monitor and then downscale it using Intel Graphics Command Centre. You can do the same with Nvidia DSR if that is available to you.

Lowering your UI scaling below the standard 100% might lead to display issues or very small text/icons that could be difficult to read, especially on higher resolution displays. Always back up the registry before making any changes. You can do this by clicking on File > Export in the Registry Editor and saving a copy. The custom DPI settings are not officially supported for use below 100%. If you run into any usability issues after making these changes, you may want to revert them.

Some applications allow you to override high DPI scaling settings, which might work for specific programs:

1. Right-click on the application executable or shortcut.
2. Select Properties.
3. Go to the Compatibility tab.
4. Click on Change high DPI settings.
5. Check the box for Override high DPI scaling behavior. Scaling performed by: and choose Application, System, or System (Enhanced) from the dropdown.
6. Click OK to apply the changes and launch the app to check if it makes a difference in appearance.