If that's your personal experience then it seems you do not have any relevant experience at all developing and maintaining software projects, specially if they need to be cross-platform and cross-tech stack.
For example, it's clear to anyone with any basic experience that providing an abstraction over C++ compiler's so that you can ensure your C++ project can and does build successfully regardless of C++ standard, compiler make and model, and eve os and os distribution is extremely valuable.
Can you show me a Makefile that handles that?
With Cmake you get the exact same C++ project building flawlessly on macOS with Xcode and clang, windows with any version of MS Visual Studio, and of course any linux distribution.
You just download the project, run Cmake to generate a makefile, and build
How do you expect to even run a Makefile the same on all those combinations?
There are very good reasons why Cmake is the de facto standard.
Writing makefiles is extremely repetitive and tedious and error prone: precisely the kind of thing to automate. Not just makefiles mind you, cmake is designed to automate all sorts of build parameters.