I can see that systemd as a piece of software has many benefits. However, as a software project, the attitude as you mention, is a major problem. In my one single minor interaction with systemd people, I already agree with this criticism:
"My experiences with systemd's Debian maintainers (and, indirectly, systemd's upstream) have been far from satisfactory in this regard. Instead of taking a flexible approach, and being willing to provide a range of glue facilities and approaches for different daemon upstreams, the systemd community seems doctrinaire. Daemon authors are expected to do as they are told by systemd upstream, rather than systemd upstream making things comfortable for daemon developers.
This is IMO the opposite of the proper attitude."
(from https://lists.debian.org/debian-ctte/2013/12/msg00182.html)
This counts as a "technical reason". Though not directly about the software itself, a project with such an attitude should not be relied on because the people in control do not have your best interests in the long run.
People who support systemd are not launching personal attacks, calling for physical harm against non-systemd supporters. This is a unidirectional attack. And it needs to stop.
Has this ever been substantiated? From my understanding, the "death threats" were more along the lines of people saying awful things like "I hope Lennart gets run over", not "I am hiring someone to shoot you". Lennart made a comment about a bitcoin collection, but provided no actual proof. Personally, I'm skeptical - I've seen quite a bit of vitriol about systemd, but never anyone campaigning for bitcoins to hire a hitman. It seems like a rather easy way to bring a lot of discredit to your detractors.
Even the former is obviously not acceptable, but no one is being done any favors if we suddenly conflate an offhand mean spirited comment with actual death threats or attempts on someone's life.
Edit: Someone linked the actual conversation - http://logs.nslu2-linux.org/livelogs/maemo/maemo.20130215.tx...
It's obviously a joke and not an actual attempt to hire a hitman. They shortly after proceed to talk about how Red Hat has replacement clones if anything were to happen, anyway.
Is it a shitty joke? yes. Is it mean spirited? Yes. Is it the same thing as actually trying to have someone kill the man? No.
Yes, it is clearly a joke.
What???
Recently, people started collecting Bitcoins to hire a hitman for me (this really happened!).
https://plus.google.com/+LennartPoetteringTheOneAndOnly/post...
No bridge is sacred enough to warrant physical threats when burned. No attitude poor enough to elicit the response that this did. It's bloody software.
Worse. It's bloody open-source software.
You don't like it, you fork the last version you did and start from there. If enough people agree with you, you'll be fine. If not, you are probably wrong.
Looking from afar, you'd think this was some tiff over imaginary lines on a map or something. Now that would be silly.
Gentoo is waiting to welcome all the systemD haters. OpenRC is going strong.
We also support systemD as well because USE flags rock.
In fact being able to see the sysV and systemD init files side by site was what finally convinced me it is an improvement. An improvement with many questionable additions... Like free money attached with losing my 25/20 eyesight to normal 20/20 or some other minor debilitating affliction.
From what I've seen the good intentions behind systemd were marred by the fact that when it was announced the (mostly skeptical) responses to it were met by systemd supporters who held the attitude 'we're saving nix, join us or nix dies', and this has created the current atmosphere of debate.
While these death threats and the like are in no doubt horrible, it seems that some bridges need to be built between the people who support systemd and those who do not, because the attitudes on both sides of the argument are rather poor, and this makes the open source community look even worse.
Edit: I said nothing about systemd users currently making threats, rather that their attitude at the beginning of the project at some level caused the response that we see today. They are not completely to blame, as are not the people who are against systemd and do not send death threats. Regardless, it seems that recently, HN only supports the idea of 'there is no gray, only black and white'. People like these are the reason why the systemd creators cannot engage in debate, because on both sides the people who shout the loudest win out over the reasonable voices.