gtk/gnome can't even decide on how applications behave in 3 era. with each release experience is doing 180. not to mention, they deviate from how other software works in a manner where pure gtk or qt application feels more at home on windows than it does on gnome. any cross platform app can't even start to follow gnome hig and not alienate 99% of the user base.
off course, your claim will be valid if you say that x is not stable version, but 3.x. that simply begs for question, are daily gnome builds now what 2.x used to be? and... when whole user experience stability doesn't matter, how can small things like api/abi in zip app