From my local informal sample, PulseAudio broke things for more than 50% of people, and "fixed" things, in the sense that sound began working properly when previously it hadn't, for less than 10%. Worse, it made diagnosing sound problems significantly harder, because it added another abstraction layer which has to be isolated in a divide-and-conquer strategy. Locally my solution was to disable PulseAudio and hope that I don't wake up one day to find that Lennart has persuaded Red Hat/ Fedora to disable the non-PulseAudio support in my audio apps.
Lennart should have concentrated on the part of the problem where he has relevant expertise, which is the network layer. If he'd built a fast and reliable framework for seamless network audio then people might entertain the idea that it's worth some disruption to get it onto everyone's desktops. But instead the argument seemed to be that Lennart would "fix" local audio (which was just coming together nicely with better ALSA drivers and dmix). He has comprehensively failed to do that.
Indeed Lennart has spent a LOT of time moaning at ALSA developers, often based on entirely false premises about how audio actually works on hardware people own, and he did not need to build yet another audio API to do that. If Red Hat had paid him to spend some time herding cats over at ALSA I'd be overjoyed, but instead this seems to have been merely a fortuitous side effect of the otherwise less than successful PulseAudio.