If that was the point you were trying to make why didn't you actually write it, instead of going on with a load of nonsense about users having to worry about which DE toolkit an application was built with?
Why do a preponderance of apps found within most repositories feel the need to describe themselves, first and foremost, in terms of which toolkit or DE they are based on? 'OMG! I found a Gnome3 checkbook manager!'
It isn't nonsense; Its a description of a social malady. FOSS desktop systems have no shortage of them. Unlike the moblile space, their primary movers are wedded to the greybeard hacker/sysadmin concept of what an OS should be: A server with a layer of foamy GUI fluff on top that can be disposed of or ignored or replaced at a moments notice.
I say, lets replace them; make them irrelevant. If Android completely mopped up all the (residual) Desktop Linux market share tomorrow (even from Ubuntu), I wouldn't shed a tear.
It's not even a very good one point - given the vast difference between Linux and Windows' *minimum* memory usage there's plenty of room for an Ubuntu box to load the toolkit from another DE without even using up the minimum memory usage for a Windows 7 or 8 box. Not to mention that different Windows applications use multiple different GUI toolkits, so your average Windows box in use will need even more memory to work.
If you want a real world example: I'm running 64-bit Kubuntu 12.04 with bells and whistles like desktop effects turned on. The computer's been up for nearly 2 days, in which time I've run applications using both KDE/QT, GNOME/GTK and Mono .NET GUI toolkits. I have Firefox running currently and memory usage is only 1GB, that's half the *minimum* requirement for 64-bit WIndows 7 or 8.
Mono, LOL.
OTOH, my 2012 model ThinkPad i5 running Ubuntu 13.04 uses 12% CPU to play a low-bandwidth voice MP3 while the notorious Gnome System Monitor shows up as 15%. Memory use is 2GB + 500MB swap for 20 very simple web pages in Firefox plus Rythmbox plus GSM plus CLI; I am using the defalt vanilla Ubuntu apps and preferences. Its on-par with OS X for RAM use, and very inefficient compared to the CPU usage on my Macbook despite the Macbook being a 2007 model that's less than half as fast in raw power.
That's not to mention all the hardware integrations it got wrong (of course, its mainly sound and visual-- but who really needs those when you got an ethernet port?!!).