In my mind CMake and Meson are tools for engineers to use in solving problems. If one tool needs some support tooling in order to be usable, then I'm intrinsica

In my mind CMake and Meson are tools for engineers to use in solving problems. If one tool needs some support tooling in order to be usable, then I'm intrinsically less interested in using it simply because there's some extra stuff I have to bolt on before it becomes useful. So I don't see why you think it's "the wrong question" here. Another poster has explained the IDE support is about IDEs being able to parse CMake files, and I can say that back in the day before CMake IDEs would parse the C/C++ directly using a compiler to output an abstract syntax tree that they would use. So for example Eclipse has this notion of "Build configurations" which allows you to control how this parsing occurs and which files the parser considers valid and what symbols are predefined. Which is IDE support very much like you're looking for from CMake. I worked with it for several years at my last job to provide support for other engineers working with a Make-based build system.