Where are the advanced OptiX denoiser settings like radius, strength, feature strength, etc. in 2.91? They were in the view layer settings in 2.83, but I can't find them any more.
Figured it out. These settings are only for the NLM denoiser, not for OptiX (nor OpenImageDenoise). I somehow misread the docs at https://docs.blender.org/manual/en/latest/render/layers/denoising.html.