Exactly my point! I have been using asterisk since 2007. Around 5-6 years ago, I had to come up with a resilient auto-deployment of asterisk with some custom modules for a client.
The custom modules were never released in the open. But, one of the primary pain points for me was to tap into the autotools and create branches for
configure -> test (custom modules) -> integration test (full asterisk) -> build/reject -> private release.
So, I didn’t swap out autotools. I created a supplementary CMake based system to smoothen the process.
I don’t envision removing anything. What I am proposing is for CMake to exist along-side.
Also, about “Cross-Platform”, yes! CMake does make it easier to enable platform specific branch selection for the building phase. I am not saying autotools can’t. But, CMake makes it easier.
At any point, if new developers are going to contribute, CMake would be easier to follow along.