I think you may be the one overstating things. Where I work, a biomedical device firm, for every one app written in C++ there is either one python or matlab prototype of it and 5 python/matlab apps to test it/show it off. I'm sure for other places that number is far higher. I honestly don't see how you could quickly prototype sufficiently complex ideas any other way.
Better said, I can build a working Kalman filter, load saved patient data to it, create a primitive db, save output data to said primitive db, build a primitive, but functional enough that non-technical people can use it, GUI, from scratch, to plot said output data in Python all in a couple hours. Can you do that with C++ for the same time frame? Heck can you do it within an order of magnitude of the time I used? If you can't, why should you be spending an order of magnitude more money for it?
Also note that Blend has first class support for C++/CX projects.
https://moderncpp.com/2017/08/25/cppwinrt-2017/
Of course most developers using C++ with UWP is Microsoft itself, for stuff like XAML engine and the new Visual UI composition engine, and game devs.
XAML is also the official replacement for MFC.
As I mentioned in some other thread today, there is hardly any pure C++ application nowadays on Windows, they are mostly a mix of .NET and C++.
Adobe will never rewrite Photoshop in Rust or whatever. If you thought burying COBOL was hard.. C++ will outlast humanity.
I can already hear the Alien scientists: "An amazingly intricate and convoluted language for such a primitive species. The mismatch between their mental abilities and their language might explain the bug which caused the incident.."