I don't think it's any more stable, dependable or predictable than any similarly mature Linux distro. It's just a preference, perhaps with a sliver of contrarianism.
I never felt comfortable managing openbsd, but linux has repeatedly and gratuitously changed all the management tools, so now it’s easier for me to get around an openbsd box, despite using Linux daily, and openbsd maybe twice a year.
(It’s a serious question. I’m strongly considering switching to one of the bsd’s at this point.)
Are you not so subtly referring to the systemd fiasco? That was about, if not over 10 years ago. I also don't think it matters. Change is not a bad thing, and that change is not as hectic or constant as you seem to imply.
If you really want a Linux distro that hasn't changed at all in the past 30 years, Slackware might be your bets bet, but I don't think that 'having not changed in the past 30 years' really makes sense as a metric.
Personally, I'm a fan of Alpine and Void Linux, and I also run NetBSD. FreeBSD seems too 'messy' as someone that likes minimalism, and OpenBSD's security focus is misplaced IMO.
Was deprecated ~20 years ago. Not a recent change.
> selinux vs cgroups vs ???
This doesn't make any sense? It's like writing "network drivers vs. X11" in OpenBSD.
Wayland, ACLs, SELinux and cgroup are all just options, none are forced.
For instance, some systemd-login thing broke compatibility with xscreensaver on my manjaro box 6 months ago.