For me, sanity is the main selling point. Make has meaningful space/tab distinction - that's quite enough to disqualify it as hopelessly mad in my book. And then autoconf is just baroque.

CMake only helps a little bit (it's still very old and has way too many warts). But Meson is very pleasant to work with.

One selling point seems to be speed: https://mesonbuild.com/Performance-comparison.html