if you click on a note, the note gets selected. If you click inside an empty place in a bar, the bar gets selected.
If you click at the clefs in Galleyview at the moment, you select an object behind it that you don’t see, so it isn’t that useful. Wouldn’t it be more logical to select the whole stave, if nothing is selected?
If some notes/bars are selected, this would select the same rhythmic position on another stave. With Ctrl you can select non-adjacent staves