Leveraging compositional abstraction doesn't change what you use the thing for. I use cmake (well I don't often, but when I do) to build my projects. How it accomplishes that is if little concern.

> I use cmake (well I don't often, but when I do) to build my projects.

no, you don't

remove from your system make (ninja, msbuild, ...) and see how cmake builds your project

>see how cmake builds your project

Yes exactly when you remove a piece of the build system the build system stops working.

When I use bazel I need python installed or it doesn't work. That doesn't mean my build system is python. It means my build system takes advantage of python. Same for cmake and make.

I'm sorry but make is not part of cmake build system. It predates cmake by decades. It is true build system used in by itself

Yes. Make is a build system. Cmake is also a build system that leverages make. This means that from the perspective of a user of cmake, make is a component/dependency/part of cmake. make can be used independently, and is absolutely developed independently, of cmake.

But when you remove a dependency of a tool you can expect the tool to stop working. That doesn't mean that the tool doesn't do what it says it does.