There must be something terribly wrong in the minds of people who design filepickers. My favorite complaint about GNOME being way too dumbed down is the impractical filepicker that doesn’t let you type the path to your file. If it’s too deep in the filesystem, you’ll have to navigate the entire tree to reach there instead of simply typing or pasting the complete pathname. The simple conclusion? KDE was more intelligently designed, bla bla bla.
…it seems that the folks behind KDE weren’t so happy about GNOME having the worst filepicker. But instead of simply copying the design (That wouldn’t be creative, right? There are always new ways to do bad things) they decided to remove the direct root directory access, as you can see in the KMail attachment filepicker screenshot below. So you can either type (or paste) the location, using this unique feature that GNOME didn’t care to offer, or navigate your way back from the home directory to the root directory and then to the place you want. How clever.