Mac Studio not displaying native 5120x1440 resolution on Samsung Odyssey G9

Hey everyone,

I am having an issue with display scaling on a Mac Studio (M2 Max running macOS Sonoma). I have it hooked up to a 49-inch Samsung Odyssey G9 ultrawide monitor using a certified Thunderbolt 4 to DisplayPort 1.4 cable.

In System Settings > Displays, macOS only gives me low scaled resolutions (3840x1080) instead of the native 5120x1440 at 120Hz/240Hz.

The aspect ratio is completely warped, and circles render as wide ovals. Because the horizontal scaling is stretched, calculating geometry for cockpit views and field-of-view angles is completely off when compared to standard monitor calculators, you can check this tool to see the exact geometric distortion difference between standard 16:9 and native 32:9 ratios.

I tried using BetterDisplay to force an EDID override, but the aspect ratio still reverts after every system restart. Has anyone found a permanent fix for macOS locking out native 5120x1440 resolution over DisplayPort?