Hi,
I just tested the same scene to make a fps comparision of Unity 2022.3.35f1 vs Unity 2018.3.1f1 testing OpenXR and SteamVR, both Unity versions using Medium Quality settings.
Results :
Unity 2022 with OpenXR Multipass got around 35 fps. EDIT : for some reason now gives me 70+
Unity 2022 with SteamVR Multipass Mirror View Mode to Right got around 35-70 fps, unstable fps
Unity 2022 with SteamVR Multipass Mirror View Mode to OpenVR got around 70+ fps
Unity 2018 with SteamVR Multipass or Single pass got 85+ fps