I agree. I don't understand how people prefer buildroot. Buildroot feels like an adhoc system of glued together Makefiles, whereas yocto actually feels like it was built for purpose.
Bitbake doesn't model all changes that affect packages, so after certain changes, some packages that should be rebuilt, aren't. It is especially prone to happen when changing Bitbake variables (example: MACHINE_FEATURES), and these are a quite common way to change things about the image being built.