Re: What about QT?
Qt is an application development framework first and foremost. It has a very nice UI toolkit and lots of cool features to make it easy to write interactive apps that run fast and respond well, but it's very focused on software that presents a graphical UI that you interact with (interesting fact: Qt is used in a lot of in-car entertainment systems, precisely because it's so good at GUI stuff on relatively slow hardware)
.NET isn't really comparable, as it's a runtime and a general purpose programming library (like Java). You can use it to make servers, clients, web-apps or desktop apps. It doesn't have a single UI toolkit, so you have to make a choice between them (of the available ones, only the Windows-only UWP comes close to Qt, but Uno could have potential).
I think both are great technologies, and I've written apps for mobile and desktop with both of them. There's things to like about each: C# is a more productive language than Qt's C++ (speaking as someone who had decades of experience with C++ and came to C# relatively recently), but on the other hand, Qt's QML layout system (and its use of JavaScript for tying together stuff that's a little more complex than a binding) is so much more developer-friendly than the XAML-based schemes you tend to see on C#, Net applications.
The FOSS puritans don't like Qt either, by the way - I can't remember what the reason was, something to do with its dual licencing where commercial customers got features first, but I find those people tend to do much more talking than actual programming, and thus are really only in a position to advise on political, not technical matters.
Biting the hand that feeds IT
