You should probably be using masks, and using layer Groups with masks and not the Eraser. An ancient tool the Eraser. Masks can be 'applied'.
Yeah, I know about that one but its not what I want. I do a lot of speed painting and quick concept art that requires a lot of quick changes. I usually paint, erase, paint again, erase again, and so on with quick paintbrush strokes and often I need to erase the same area from more than one layer. If I use a group mask I can erase using it but I cannot paint under the masked areas and in order to do so I have to apply the mask to each layer and then remove it. Not very good.
Ideally speed painting can be really speedy with multiple layers if used in this way: having the paint brush selected and being used, Ctrl click to auto select a layer to paint, or Ctrl + Shift click to auto select multiple layers to erase holding E, releasing E gets back to the brush, then Ctrl click to auto select a layer, and continue painting.
There are 2 problems that stop the flow of this workflow, one is the inability to quickly erase from selected layers (and this is what I'm requesting) and the other is the lack of a quick way to auto select just one layer when there is multiple layers selected.
When we have multiple layers selected a click over the pixels of a layer on the canvas should select just that layer but it doesn't - all of the selected layers stay selected. We have to hold Ctrl + Shift to auto deselect a layer, and then Ctrl + click the same layer to get only that layer selected which is kind of slow. I know that click to auto select a layer when multiple layers are selected may interfere with click and drag to move but just a quick click without holding should do it or at least alternatively it can be used with a modifier key to prevent accidental move.