Working on a couple of projects, I really needed something like this, especially for coloring on layers underneath a greyscale sketch ,which is set to multiply ( I don’t necessarily want to compress the levels into just white and black) . I would constantly have to hide it (or isolate current layer) in order to pick the actual color I’m working with.
I know there are those options like “pick from this and below” but I find it a bit less practical than just letting the app ignore reference layers.
I could in that case set the grayscale sketch layer to “Reference” and set the eyedropper mode to something like “all except reference” . Then the process would be a lot more streamlined.
Hope this made sense and be considered.