Update: DXVK-NVAPI 0.7 was also released just now with NVIDIA Reflex for D3D12 support using the VKD3D-Proton entry points. There is also support for Latencyflex on non-NVIDIA GPUs for a few games via spoofing the Pascal architecture for non-NVIDIA GPUs. Plus various other updates and improvements.
Are you sure?
IIRC enabling reflex can actually increase latency in some setups, I’ll try to find the details.
Latencyflex didn’t work any other way except with proton. But installing it and getting it working was not simple. But that wasn’t Nvidias implementation yet.