I think he’s saying that if you collapse all, he would expect it to “reset everything” in a way so that if you then click expand an item, it would go only one level deep again. Either way has some logic to it, it just depends what one thinks is “intuitive” to them.
So, recapping:
• If you Option/Ctl click on an expansion arrow, it expands all nested levels.
• If you Option/Ctl click on the downward arrow, it collapse all, and resets as @DGSketcher is asking.
I’ve also noticed that the same behavior applies to tag folders in the Tags palette. Very useful now that I’ve found it.