From a language perspective the only one I can think of is that C++ coroutines are much more powerful than what Rust gives you at the moment, even though they are very footgun-dense (quelle surprise).
But yeah, overall there is very little reason to pick C++, especially now it's feasible to translate existing C++ to other languages.
I don't get this in particular. All of these devices have C, which seems like a better fit for the problems you'd likely have on a platform that's small or obscure enough that it hasn't got something nicer than C++
For anything weirder than that (PIC?) where Rust is no option, it's not like you have no choice either: You can just pick C.
But isn't using Qt like learning a whole new layer of language on top of C++, the meta compiler, signal/slot system etc and then Qt have its own set of standard classes like QString (instead of using std::string)
The signal/slot system actually doesn't need MOC anymore, and the custom container classes are pretty obvious.
That said I think some Rust GUI frameworks are finally starting to mature. I quite like gpui-kit (formerly gpui-component). Maybe not as easy to use as Qt but it doesn't matter so much now with AI.
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