Once we have that layer("LayerName") "accessor", we would still have to write
let LayerName = layer("LayerName") to have a variable called LayerName for use with withLayers. Otherwise you would have to write withLayers([layer("LayerName")], ...), which is both wordy and typo-prone (if you type withLayers([layer("LayerNaem"], ...) a new layer would be created).
Once we have that
layer("LayerName")"accessor", we would still have to writelet LayerName = layer("LayerName")to have a variable called LayerName for use with withLayers. Otherwise you would have to writewithLayers([layer("LayerName")], ...), which is both wordy and typo-prone (if you typewithLayers([layer("LayerNaem"], ...)a new layer would be created).