I found it actually captures HDR but the whole range is mapped down (probably intended) to sRGB in the captured image, disregarding the HDR Settings which results in a washed-out image if you have anything set other than 0 black and 100 brightness. (=> if HDR had a range from 0 to 1000 and sRGB 0 to 100 then an image with black at value 100 and white at value 500 would map to 10-50 instead of 0-100)
It is much better in survivor though than how it was/is in fallen order. at least the captured image now has all channels synchronized (same mapping) in a linear fashion while FO had a different mapping for each color with differently pronounced curves.
if you want to capture actual HDR images you can do this on Windows via the XBox game bar which saves it as jxr in addition to a mapped png
