You can use Gamescope to get HDR working. On Steam games I use this template as the launch option for games (2160x3840 is the resolution, 240 is the refresh rate):
DXVK_HDR=1 gamescope -f -H 2160 -W 3840 -r 240 --hdr-enabled -- %command%
You can read more about it here: https://wiki.archlinux.org/title/HDR_monitor_support
Can you provide a source? I haven't heard that perspective before but it sounds interesting