Virtual Reality

The 120hz was disabled by the ~~os~~ software so far. The hardware was cabable of 120hz from the beginning, as a matter of fact even the Quest 2 supported 120Hz already. So some people were infuriated when Quest 3 was released with only 90Hz mode activated...

John Carmack recalled in some interview that shopping for small displays based on latency and framerate was a huge pain in the ass until they started talking directly to manufacturers. LCDs aren't limited to television-based rates by any technical obstacles. That's just the goal, by default. As soon as he spoke to someone in a factory, they offered to set it as high as he wanted and see if it worked.

Any active-matrix LCD panel might handle changes approaching the gigahertz range. How many frames per second that works out to depends on pixel count. (For 1080p it'd be 500-ish.) But the liquid crystal elements themselves probably can't switch fast enough for that to matter... and ensuring that kind of bandwidth to the display is nontrivial... and sending any signal, more often, generally takes more power. So for head-mounted gizmos the math favors steady framerates as low as people will tolerate.

Which makes the slow adoption of variable framerate / variable syncing really god-damn frustrating. We have the technology to make even 60 FPS feel like real life under a 60 Hz strobe light. But no: if you put rock-steady 143 FPS on a 144 Hz monitor, there's a hitch once per second, and latency is a triangle wave.