[cycloptic]

>So you're not really allowed to solve one without solving the other

The final comments from the developer directly contradicts this claim:

>I'd be happy to review a merge request that added the ability to disable recursive search in the file chooser using a GSettings option ... I was thinking more along the lines of having a key in the file chooser settings schema that would be observed by Nautilus.

The idea there is that the key should be in a standard location read by nautilus (or some other GTK file manager) if it also decides to implement that feature. Edit: I also should note that it appears there was not even initial consensus about this, the other GTK developer seemed to be skeptical at first.