That's how I see systemd and wayland. For systemd the consensus seems to be that's it's better than the previous init systems as most distributions have adopted it. It seems we're going in that direction with wayland but we'll see how it goes.
I think the parent comment was alluding to the fact that RedHat has the ability to manufacture consensus. All the distributions use systemd (and pulseaudio and ...) because GNOME and other core components were modified to work only with systemd. So everyone agreed to use RedHat's way because there was no other way. No matter how good RH's creations might be, that's the kind of tail-wagging-the-dog power that is bad for an ecosystem.
But the point remains that, even without any ill intent, the lack of competition and compromise can produce outcomes that look like malice -- people gradually get used to making decisions that go unquestioned, and unwittingly walk all over everyone who no longer has a voice in the discussion. This pushes more people out, and the cycle of the tail winning against the dog repeats and continues.
- Audio system that ignores all the foundations of ALSA and builds Yet Another Layer instead of improving ALSA.
- Display system that leaves way too much as an "exercise for the reader".
- 10+-year-long transition periods on the above, during which nobody's use cases work well.
- Decisions made by fiat rather than by consensus.
I'm not sure what you mean by consensus, if there was consensus on everything then we wouldn't have so many Linux and BSD distributions. We'd probably have just one or two, and you'd probably be more annoyed about "wagging the dog" if that was the case.
Just one point about ALSA; most of it actually lives in userspace. The ~/.asoundrc file can specify complex routing and mixing, including the use of LADSPA filters. What's done is done, and pulseaudio is reasonably usable now, but IMO we'd be much better off if the work that went into Pulseaudio and jackd instead went into the ALSA userland.