I'm not that enthused about where Qt is heading but it's arguably in better hands than GTK+, that's for sure. First, Qt isn't strictly tied with KDE - it has its own life by itself, without KDE libraries at all, and a vibrant ecosystem that uses it for automotive and cross-platform desktop apps. Second, while the Qt Company has decided to stop releasing LTS releases as open source, KDE has a binding agreement that allows KDE to release Qt on a BSD license, were the Qt company intentioned to close it down(https://kde.org/community/whatiskde/kdefreeqtfoundation/). Since the whole LTS shenanigan happened, KDE has shown to be quite competent at maintaining its own set of patches for Qt5, which most distributions nowadays have adopted.

If Qt were ever to become closed source again, it would probably face a very strong competitor in a BSD or Apache-licensed fork from KDE. The Qt Company sells its licenses mostly to people that want to use GPL-covered Qt modules in closed source apps, so they really cannot let that to happen.

Yeah, the KDE Free Qt arrangement is pretty unique and makes it significantly less likely that there will be a rapid dropoff in Qt open source. This became important because the modern Qt company is awful.

That said, I still think the direction of Qt has kind of sucked. QtWidgets is mostly stagnating, and Qt Quick is not really appealing to me…

On the bright side, PySide has finally been adopted by Qt as its official bindings, and it has made PyQt largely redundant. I find it simplifies a lot Qt app development on desktop, and it has the potential to attract a lot of new developers to the platform.

While QtWidgets are stagnating and Qt Quick is arguably very "HUD"-centric and barebones for desktop development, there are nice portable UI toolkits such as KDE's Kirigami popping out that are very usable even without KDE.