Qt has always been available under a dual license. A commercial one, and... "one intended to be open source". If you wanted to make your application open source you could use Qt, and if you wanted to keep your application proprietary you could buy a commercial Qt license.
Back when KDE was being developed (which was open source), although the Qt source was available Qt wasn't free software nor OSI compatible. Back then it was owned and developed by Trolltech ASA, a Norwegian company (it was eventually bought by Nokia). Because it wasn't considered free software nor OSI compatible, certain distributions such as Debian didn't include it in their free repository and the FSF claimed it was incompatible with the GPL. So you had to grab it from non-free. I remember compiling 1.4x myself, same with KDE. It was eventually released under the QPL which wasn't considered GPL compatible by the FSF. Eventually it was also released under the LGPL. However while all this relicensing was going on (and it took various years), GNOME was already being developed, which was taken under the wing of the FSF as the free software desktop. By the time Trolltech had released Qt under the QPL and GPL, we already had a fractured "Linux" or open source desktop.
During the early versions of GNOME and KDE (before Web 2.0) ie. KDE 1, KDE 2, KDE 3 and GNOME 1 and GNOME 2 KDE was seen as a Windows esque desktop environment with lots of bells and whistles. As you say, it had large support in Germany and SuSE. Meanwhile, GNOME was regarded as a more Apple-esque desktop environment (like OSX or macOS as its called now) and the other main large commercial Linux distribution RedHat and main competitor of SuSE had GNOME as default desktop environment. GNOME also had HIG when KDE didn't yet.
Meanwhile, as you put, GNOME's libraries were LGPL and were therefore more proprietary-friendly because it doesn't require the fee for a commercial license which Qt has. For bigger companies that might not be a large barrier of entry, and you can find an ample amount of high commercial quality applications based on Qt.
A comprehensive history is written on Wikipedia [1]
Incomplete lists of software using Qt (doesn't contain discontinued software such as e.g. Opera for Linux) [2] [3]
Back when KDE was being developed (which was open source), although the Qt source was available Qt wasn't free software nor OSI compatible. Back then it was owned and developed by Trolltech ASA, a Norwegian company (it was eventually bought by Nokia). Because it wasn't considered free software nor OSI compatible, certain distributions such as Debian didn't include it in their free repository and the FSF claimed it was incompatible with the GPL. So you had to grab it from non-free. I remember compiling 1.4x myself, same with KDE. It was eventually released under the QPL which wasn't considered GPL compatible by the FSF. Eventually it was also released under the LGPL. However while all this relicensing was going on (and it took various years), GNOME was already being developed, which was taken under the wing of the FSF as the free software desktop. By the time Trolltech had released Qt under the QPL and GPL, we already had a fractured "Linux" or open source desktop.
During the early versions of GNOME and KDE (before Web 2.0) ie. KDE 1, KDE 2, KDE 3 and GNOME 1 and GNOME 2 KDE was seen as a Windows esque desktop environment with lots of bells and whistles. As you say, it had large support in Germany and SuSE. Meanwhile, GNOME was regarded as a more Apple-esque desktop environment (like OSX or macOS as its called now) and the other main large commercial Linux distribution RedHat and main competitor of SuSE had GNOME as default desktop environment. GNOME also had HIG when KDE didn't yet.
Meanwhile, as you put, GNOME's libraries were LGPL and were therefore more proprietary-friendly because it doesn't require the fee for a commercial license which Qt has. For bigger companies that might not be a large barrier of entry, and you can find an ample amount of high commercial quality applications based on Qt.
A comprehensive history is written on Wikipedia [1]
Incomplete lists of software using Qt (doesn't contain discontinued software such as e.g. Opera for Linux) [2] [3]
[1] https://en.wikipedia.org/wiki/Qt_(software)#History_of_Qt
[2] https://en.wikipedia.org/wiki/Qt_(software)#Applications_usi...
[3] https://en.wikipedia.org/wiki/Category:Software_that_uses_Qt