Yes? Well, partly.
For systemd and pulseaudio, the systems they were replacing legitimately had major problems. There were variants and workarounds that fixed some of these, but no holistic solution that I've ever heard of. There were just so many limitations if you maintained any degree of compatibility. People were (understandably) unwilling to start over and rearchitect something that desperately needed rearchitecting. Poettering designed and implemented replacements that were substantially better, and worked. Worked well, in fact. That's the great ideas & implementation part.
Much of this was enabled by a willingness to throw out compatibility with nearly everything. Backwards, forwards, sideways. If I were making a bold and breaking change like this, I would sacrifice compatibility but try to make up for it by bending over backwards to catch as much of the "once working, now broken" wreckage that inevitably piled up as I could, by creating shims and compatibility stubs and transition mechanisms. I'd certainly listen to people's problems and try to work out solutions.
Poettering, as far as I can tell is more of a honey badger (excuse the dated meme). He just doesn't give a shit. If your stuff doesn't work in the brave new world, then your stuff is broken and is going to have to adapt. That's the bad execution part. (Which is not to say that bending over backwards is always the right approach; it can massively increase the burden on the new system's implementer, to the point that it never happens. There's a reason why Poettering's stuff is taking over the world.)
As for bad interface, this is a lot more subjective, so it's easier to disagree. But the tools to configure and use the new system are done in the style of an isolated cathedral. The tools do a ton of stuff, but they do it all in a new way, and that's great once you learn the blessed paths and internalize the new architecture. But all of your existing knowledge is now useless, and you can't flexibly combine and extend the functionality with the usual tools you'd use (bash, grep, awk, find, sort, tee....) The main functionality of the new system is not new — none of this is really adding fundamental new capabilities, it's just improving things that were already being done. But the way you interface with that functionality is all new, even though it could have been exposed in ways at least a little more unix-like and composable. Instead, the tool author determines all the things you should be doing and gives you a way to do them. If you want more or different, then you're doing something wrong.
Normally, I'd expect something like this to die out as it rubbed up against the surrounding functionality. "Great system, but too much effort when we keep having to fix thing after thing." Surprisingly (to me), in systemd's case in particular, what has actually happened is that the cathedral just keeps expanding to swallow up enough of its surroundings to keep from being ejected.
Maybe it's sour grapes, but my guess is that this was only possible because the previous systems were so bad. esd was a nightmare. sysvinit scripts were baroque and buggy and error-prone. Sure, the first 80% was just plain simple shell scripting. But everything did the last 20% slightly differently or just punted. It was all buggy and idiosyncratic and failed intermittently. Supposedly some of the init system variants managed to corral it all together enough to do actual dependencies and get decent startup speed, but I never used such a system. And based on the quality of the init scripts I've seen from random packages, I'm guessing the successes only happened when a relatively small group of people wrote or repaired a metric shitload of init scripts by hand. And even then, systemd provides more in its base functionality set. Architecturally, it's really quite nice.
