To be specific, the question can be asked as: Can you replace a Linux kernel build system with a build system that is mainly based on CMAKE?
I know CMAKE is good for building a cross-platform package, like a library or an application. But I suspect it is not good for a system consisting of a few components and you want to advance the development of each components separately. In another words, CMAKE probably is not good for a build system that is focusing on composition of a system from different components.
To create a build system for system composition, it may be better to use the git-repo tool to manage the top-level composition. At the top-level, it is more about pulling packages at different hashes into a system layout. After that, the further building steps can use CMAKE or any other build techniques. As an example, Legato comes to mind.
To build system experts, what is your opinion?
On the list of related questions the question "which suits linux" links to two interesting other options - scons and waf.
Both scons and waf, are a good candidate to be a buildsystem tool: They have the full capability that a fully-fledged programming language owns. That makes them well suited to write a buildsystem that can compose the system anyway that you can write a program to represent. And they by themselves are a build system, no requirement for a separate build system. Compare: autotools, cmake, qmake all generates makefiles and requires a separate make system to do the build.
Back to the original poster's question: If the project team is good on Python, then use scons or waf but not cmake. If your team members are really good at cmake handling but not python, why not cmake.