ray tracing denoiser option in the GUI is counterintuitive such that it seems broken
Denoising only kicks in when the number of samples or progressive passes exceeds a threshold.
However the button to enable denoising is always present, even when oidn is not configured into the build, so most new users think it doesn't work.
We need to clean up the GUI and modes to clear up the confusion. At a minimum the pop up help for the denoiser button needs to explain what else needs to be done to make it take effect.
See also: #18414 (closed)