[jraph]

Alsa just worked but had limitations. Some apps grabbed sound and you could not play sounds from other apps. Often, one app could play sound at a time. It depended on whether your sound card could handle several streams IIRC. Each major desktop environment had its own sound server to work around these limitations (KDE's aRts, Gnome's ESD).

PulseAudio let us have a common stack instead. There were bugs (PulseAudio was probably a bit buggy at first, and also hit audio driver bugs because of the new ways of using them). The transition was rough and PulseAudio is not perfect too but is it there for reasons and solves many issues.

Now it is being replaced by PipeWire, probably for the best (more efficient, can replace JACK too, making sound management much easier on Linux), but PipeWire leverages experience from PulseAudio.

I lived the transition to PulseAudio and it went well for me and probably a lot (the majority?) of people. Some things could probably have been handled better, especially the (too early?) transition. I think PulseAudio still is/was a good thing.