CMake may "just work" without you investing much/any effort - in the future.
For now, the situation is that if you invest in your CMake - blood sweat and tears - then the build itself will "just work" on many/most/all platforms. Which is already pretty good - compared to being stuck with Makefiles.
Also, CMake is essentially its own debugger, because almost all state is just a bunch of string variables.
Nobody really wants to focus too much on build configurations when working on things, they should 'just work'.
And CMake, although I am using for a long time already, is not the offering this 'just works' experience I am afraid. It is so easy to introduce side-effects, and figuring out the intended way to include a project can be a big pain when documentation is sparse. Sometimes I wished I had a CMake debugger. And with modern CMake I feel like this got worse to some degree.