A lot of projects would be better served with a plain Makefile although for widely posted projects something is required.
Qemu has used a single readable POSIX shell script for configure although recently most of the tests are in meson (avoiding some Makefile shenanigans in the process). While it's a new syntax to learn at least the intent is clear and reviewable.
Is the hardware support for Raspberry Pi still out of tree or can I use an upstream build now on my Pi 4?