No, it's mostly because Qt5 apps also start to use QML widgets, which are quite a bit inferior in just about everything. Higher latency, a "touch like" feel (fatter borders in general, overall lower display density), respond in a different way (scrolling), and so on.

I always was a great fan of both GTK2 (for the UI) and Qt4 (for the API). GTK3 made me switch to Qt4 for development. Qt5 brings some improvement, but as a user I absolutely hate QML.