Yes. However, the value 72 dpi is important in GNUstep/Cocoa because 1 point in
the window's base coordinate system = 1 pixel, and a point is 1/72 inch. (even
though it's an arbitrary number in some sense because no modern desktop screens
are really as low resolution as 72 PDI).
So drawing an image with 1 pixel = 1 pixel means treating the image as if it is
72 DPI, which is what the code did before my patch, i.e. it set the dimensions
in points to the dimensions in pixels.
I just checked on Cocoa and it ignores the dpi of PNG's and assumes them to be
72dpi, however it reads and uses the dpi of TIFF's exactly as GNUstep does now. In
addition, Cocoa supports multi-image TIFF's, something I would like to add support
for to GNUstep. This means we can provide high-res versions of the default artwork
which are only used when a scale factor> 1 is set.