TL;DR. The G95NC's rear CoreSync+ lighting is fully readable and mostly writable over plain DDC/CI, through three manufacturer-specific VCP codes that the monitor does not advertise in its capabilities string:
| VCP | Meaning | Range | Writable |
|---|---|---|---|
0xF8 |
Lighting source | max 17 | only 0x00 (off) / 0x01 (manual) |
0xF9 |
Lighting effect mode | max 5 | yes, in manual mode |
Short version for people who Google'd their way here at 2am: if your Mac shows the G95NC at 2560×2160 native 1:1 (tiny text) and the Scaled menu has no 1920×1620 option, it's not the dock and not the HDMI port — it's the cable. You need a USB-C → HDMI 2.1 active cable (not DP-to-HDMI, not a generic adapter). Both HDMI-1 and HDMI-2 on the monitor work once the cable is right. Scripts + full wiring below.
You bought a Samsung Odyssey G95NC 57" Dual UHD (7680×2160, 32:9). You dock your Mac (MacBook Pro M-series) through a Thunderbolt 4/5 hub. You run it in PBP 21:9 mode so the right half is 2560×2160.