The reason is likely because they are using a DP to HDMI 2.1 converter (advertised a few years back) and thus they inherit the 32 limit.
MS went native HDMI 2.1 but they probably held back because cables much more problematic when you get over 40.  Good bet LG knows this too.  And 40 is enough for 120/10/4:4:4.

It is starting to get hard to actually transmit that much over copper.  Not impossible but with the literal sea of cable qualities out there the issues compound when you are both at the technological edge of "capable" and dealing with someone who figures that $5 cable they picked up online should do the job just fine.

Just wait until we get to DP 2.0.  Same issues but more of them because the speeds of the standard are even higher.

Holy s**t! Anyone cares! This and all the others facts that only a pc nerd can understand! gamers (and even i, a pc gamer nerd) what games, not tech facts. Because 4k 120 FPS is already a bulls**t, my dream is 1080p stable 60 fps. For sure gta 6 will run 30 FPS (hopefully 4k).

No I will not give half thausand euro for this.