In the beginning (95-ish) Qt was license encumbered, there was serious agitation about KDE becoming popular while using it, leading to the very-open GTK based GNOME desktop competition. It was a big kerfuffle at the time.

See the History of Qt section: https://en.m.wikipedia.org/wiki/Qt_(software)

Also Qt is C++, whereas GTK is basically C.

100% agree, I missed that - at this point in time (and maybe still a bit today?) there was a lot of grift between C and C++ being used for Linux systems things around that time as well (including how big the resulting binaries were, because modems to download!). Thanks for the reminder.

My impression was more than a little regionalism. KDE came from Europe. GNOME came from America. Most distros that I know come from America.

In addition, Richard Stallman made lawyers nervous of KDE by claiming that using GPL libraries with Qt (which at the time was under a proprietary license with source code available via FreeQt, definitely not a FSF-approved license) meant the KDE developers had no legal right to use GPL programs at all, even after KDE and Qt were relicensed under GPL.

Stallman eventually relented and granted permission to use the FSF’s own software, but the KDE project didn’t ask for it and didn’t bother to get forgiveness from other GPL license owners. Whether they need to go through that ceremony was never tested in court. GPLv3 switched to a much more reasonable standard, just provide the source under a compatible license.

By the time the license tempest-in-a-teapot reached a conclusion, GNOME and KDE already had substantial-enough installed bases and corporate sponsors to keep going indefinitely.

GNOME was backed by RedHat and other American developers, which included the likes of IBM, Intel, etc.

The bulk of QT and KDE developers are European; the only major European distribution, SuSE, went with KDE - but apart from that, the project could never attract the same level of investment as GTK-based efforts. It’s kind of a microcosm of the US/EU imbalance in digital tech.

Add to it that C++ (Qt) was never as popular as C (Gtk) in academic circles, which are major contributors of fresh developers to opensource in general.

I don't think the reason is really c++ vs c. But the regional aspect is spot on. Also when SuSE was bought by an American company (Novell), they fired all the KDE devs.

Another aspect is the licensing, GTK was licensed under LGPL way before Qt and RMS casting doubts on the legal aspect of KDE even after Qt was re-licensed under GPL didn't help.

All these played a role in the early 00s, nowadays the problems is mostly that GNOME has many more enterprise features and integration with other RedHat products and it is hard to catch on.

Perhaps because GNOME is under the Red Hat umbrella, so perhaps other believe it will always have a large amount of resources available to it.