Considering installing build tools and makefile generators such as cmake, meson, jam, ninja, scons, etc is common developer practice, I see no problem with gnu make being a requirement, provided it's possible to build it on the target system.
I personally quit using CMake years ago; great promise but underdelivered in my opinion. I’ve moved back to hand-rolled (BSD) make files for my own projects.
To your point though - I don’t think the fracturing of (often poorly developed) build systems supports the thesis “GNU Make everywhere”.
