I use 2.4 gamma as well. While it might not be the most technically correct setting to use, it makes the image look better for me in SDR and HDR. I've noticed a few reviews mention this as well.
Does anyone here have an issue where the monitor keeps defaulting back to HDR 400 True Black? I must have set HDR 1000 in the menu at least a dozen times now but it seems to randomly switch back to HDR 400.