14 Sep 2021
Environment macOS High Sierra+ / Mojave / BigSur
Issue You would like to easily set Mac Retina display(s) to higher unsupported resolutions.
Resolution Free - RDM
Shareware $14 - SwitchResX
Root Cause macOS X only natively supports HiDPI modes on monitors with the most common Aspect Ratios.
More details - Guide: Fixing External Monitor Scaling and ‘Fuzziness’ Issues with MBP and OSX