I did formulate that badly. I did not want to say that Jetbrains and MS do not use LSPs too, but that the most important IDEs do _not_ use an LSP - Java, Kotlin, Python, C#, Rust - or add significant improvement to them - like the debugger and refactoring for C++.

And again, while (not-Code) VS may support LSP, it does not use one it for the main languages - C++, C# and F#.