> When Symbian, then called EPOC32, was developed there was no C++ standard library
There was no standard to begin with (actually the first release of Symbian and the first C++ ISO standard are pretty close on the timeline), but STL and likes existed.
Then again, Symbian was on the market until 2013, but programming for Symbian always sucked. Especially in the later years, when Nokia completely missed the advent of touchscreens, and tried to keep afloat by throwing Symbian on a touchscreen and seeing if it sticks.
Qt was always a bad strategy. Sure, in some aspects it was better than anything native Symbian could provide, but in general it was many years behind iOS and Android UI frameworks.
For example, one of the most frequent patterns in touchscreen UI design is an infinite list of views with dynamic data loading and filtering. A lot of use cases fit into this abstraction - social media feeds, storefronts, messaging apps, dictionaries, streaming music players, etc. Android supported this pattern in UI framework from the very beginning and continiously improved it, while Qt's answer at the time was "oh, just write it from scratch".
And the fact that Qt uses highly specific dialect of C++ doesn't really help adoption.
Are you sure you know what you're talking about? Or maybe you were using a very ancient version of Qt. Today's Qt C++ and QML are extremely capable. And I'm building one of those "long lists" (ListView) in my block editor[1] that was straightforward to implement in Qt.
In case you've missed, we're talking about an operating system whose last release was twelve years ago.
The first Qt version for Symbian was around 4.6, and IIRC QML didn't even exist then. The latest was around 4.8, and it did have QML and Qt Quick, but it was too little, too late.
There was no standard to begin with (actually the first release of Symbian and the first C++ ISO standard are pretty close on the timeline), but STL and likes existed.
Then again, Symbian was on the market until 2013, but programming for Symbian always sucked. Especially in the later years, when Nokia completely missed the advent of touchscreens, and tried to keep afloat by throwing Symbian on a touchscreen and seeing if it sticks.