I think I understand. Going to, e.g., Desktop > Desktop Software, then clicking (for example again) Settings on the left sidebar, then clicking Home, you will be sent back to the Desktop Software section. For me, clicking Home while browsing packages does nothing.
Either "Home" is not what that button should be called, or it should be doing something different.
In technical terms, I think each page is a GtkStack page, and the buttons on the left are a GtkStackSwitcher, so each button just takes you to a corresponding page in the GtkStack. I don't know without looking if the package browser is a GtkStack within the main GtkStack, but I suspect it is because that would explain this behavior.