desktop-GUI: I'm not a fan of Electron either, however the community seems not to be joking about picking it. It seems like most projects are going that direction. None of your arguments here are about a new projects, just about existing technologies.
Embedded: But how is that an argument for C++? I can do safe stuff in Lua without the hassle of C++ & then use C when needed.
Parallellism: Agree. Here we have a case.
Scientific: Yes, someone needs to write the underlying libraries for Python & Matlab, but if you are starting a new project, do you actually start writing a library first or do you use an existing one?
IDE tooling: Yes, good tooling can be a good argument in itself to pick a technology. With C++ maturity is as a clear advantage, however some of the languages that i listed do have quite nice tooling today, e.g. C# & TypeScript.
desktop-GUI: What community? Web devs trying to write desktop apps?
Embedded: Try to write a safe string and vector with bounds checking, or IO port access in C like in C++ type system allows for. Lua is nice for hobby, not production class hardware deployments.
Scientific: Depends, many libraries are yet to be written.
IDE tooling: Typescript and C# audience isn't the same as those using raw C++.
desktop-GUI: Yes, frontend today is a combination of Web & apps, C++ does not fit in either. UWPs can be written with JS or C#.
Writing desktop-GUI is also on the decline, however I could see potential increase in desktop-GUI-programs if governments continue to pass bad regulations of the web like content filters & link tax.
Embedded: How come C++ is not dominating embedded? According to you, it should.
IDE tooling: If you are writing a 2D-game or desktop-GUI it is.
Even though C++ is used as an important building block for other technologies, too survive, C++ must attract a new generation of developers, to continue carrying the torch & develop it further. Does it? I have seen little evidence of that. My impression is that developers learn C++ because of existing projects. Sure, there exists lots of good C++ projects out there that will continue attract developers & push the language further, but will it be enough? I'm not convinced.
desktop-GUI: Many UWP APIs are only accessible to C++/CX. Plus only UWP controls written in C++ are usable from Win32 side.
I have spent the last 4 years doing green field desktop GUIs, apparently those customers haven't got the news.
HTML5 APIs still aren't a match for plenty of native APIs.
Embedded: Religious hate against C++ from older timer devs, as discussed in several CppCon and Meeting C++ talks, e.g. Dan Saks has quite a few of them.
CppCon 2019 will change location, because they no longer can fit everyone on the old location.
Embedded: But how is that an argument for C++? I can do safe stuff in Lua without the hassle of C++ & then use C when needed.
Parallellism: Agree. Here we have a case.
Scientific: Yes, someone needs to write the underlying libraries for Python & Matlab, but if you are starting a new project, do you actually start writing a library first or do you use an existing one?
IDE tooling: Yes, good tooling can be a good argument in itself to pick a technology. With C++ maturity is as a clear advantage, however some of the languages that i listed do have quite nice tooling today, e.g. C# & TypeScript.