The folders toolbar ("tree view") is still in development, so this is mostly a note for later on:
TL;DR: Subfolders and statusbar should be in sync.
Select a folder in the folders toolbar (say c:\windows)
Uncheck Subfolders in the folders toolbar.
Result: Only files/folders that have c:\windows as their parent are shown in the result list
The currently active folder - c:\windows - will be shown on the status bar. Double-click it.
Result: All files/folders are shown in the result list ("everything")
Result: Subfolders is still unchecked.
Subfolders should be checked again. And because it's not, activating the Folders toolbar will limit the reslts again.
EDIT: Unless a keyboard shortcut is used to activate the Folders toolbar. But that's because it wasn't focused on a folder in this specific case.
BTW, Suggestion to use path ellipsis for the foldername on the statusbar. Or 'prioritize' the other statuses (?) like Match Path. They fall off the statusbar if the folderpath is too long.
I just took another look at my "sync" suggestion. The foldername is in the statusbar, even when 'subfolders' *is* checked. Missed that the first time, somehow.
So things are good as they are; suggestion can be skipped.