Software upgrades for the OnePlus 7 Pro camera are rolling out now
https://www.techradar.com/news/software-upgrades-for-the-oneplus-7-pro-camera-are-rolling-out-now
OnePlus promised it was coming and now it's here: an updated version of OxygenOS that primarily focuses on getting better pictures out of the rear camera on the OnePlus 7 Pro, particularly in low light.
In fact the OxygenOS 9.5.4/9.5.5 release notes specifically mention both Nightscape (the low light mode on the phone) and HDR as areas that should see improvements once the patch has been applied.