The lost art of creating good desktop apps.

Hello everyone I am a novice C++ developer. I would like to learn how to create good desktop applications in C++. Don't you think it's a lost art? All the applications that I use every day were created a long time ago (for example, 7zip, wireshark) And it doesn't really look like we're creating something like this today.

I would really like to learn how to create something like this and would like to hear your advice (I am especially interested in creating applications that somehow process incoming data and then output it in real time)

A few of my thoughts:

1) It seems that to create applications of this level, you need to be very well familiar with the operating system internals, and not only in the C++ language.

2) Many good applications have closed source code and we simply cannot study it, and for those applications where the code is open, it has already been written hundreds of thousands of lines, it is difficult to understand this and identify the "architectural core".

3) Many recommend "just take Qt". That's good advice (is it good?) but this is only the smallest part of the job. I think it's right to divide applications into layers and a display layer (which is why we use Qt) doesn't look too complicated. Yes, I know that the Qt ecosystem represents almost everything that is needed, but I would like to separate the UI layer and the Core layer of the application so that I can quickly change the UI layer if necessary.

4) Multithreaded model, we don't want the application to lag and generally want responsiveness speed. That's what I have the most questions about.


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