And if you recall correctly in the Debian community, adopting his systemd was a long and challenging 2-year long debate. Debian adopted systemd three years after Fedora did. Afterwards multiple senior contributors resigned from their positions due to extraordinary stress levels caused by ongoing disputes about systemd.
So when I tell you the Debian community mainly cares about servers, I'm not bullshitting you and I know who the fuck Lennart is.
His workstations, and not to be snooty about it either, it's just like some people prefer crunchy peanut butter, and some people ruin their lives with creamy.
I liked init systems of yore. I don't ask to toss out systems because its very useful in some settings, however, I prefer the init systems we had, when it comes to my personal workstation preferences.
All of my non-professional work systems are OpenBSD and I will tell you that BSD init is a friggin breeze.
Sadly that ship has sailed, but it's finally 10-12 years later that there are some niceties to systemd that make it worth it to me (systemd-resolved in particular).
Can't speak about AIX, but it was massively more used than HP-UX. Solaris was still under pretty active development and adding new and cool features in 2012, while HP-UX seemed pretty much abandoned by HP. Itanium on HP-UX was HPs last big push on HP-UX, but after that failed to catch on they seemed to give up on the OS.
They are primarily not concerned with your workstation.