Difficult to say. I will not justify why I want the numbers display. It just happens that while browsing or managing items in the desktop app, my view goes to the sidebar and misses the numbers present in the previous app. In this moment, I need the numbers to make sure I am in the correct collection or view with the expected number of items. If the numbers are not what I expect, some item went missing or I did move it wrongly, or whatever happened and I need to correct that. It's usually only one look for verification purposes, but now I have to actively look for the location to click to, than scroll down or locate the sort button and click it to get the number (which is not very intuitive).