systemd is all about making GNU/Linux the new POSIX
>If this were true, I would expect the BSD distros to consider it
Uh no. Red Hat went out its way to make systemd Linux only and through very strategic placement in some major projects (the udev dependency changed everything) got it in the dependency web so it will make more and more FOSS over time largely Linux only which guess who sells the most maintenance contracts for? Take a look at how much work it is already to port Gnome (another project Red Hat has their hooks in deep) to any other POSIX.