I don't think that's important. In practice you can also use the pulseaudio API and that will work everywhere because of this: https://github.com/i-rinat/apulse
Apulse is much more cumbersome to use and not something you can really rely on - AFAIK it was originally written as a workaround for Firefox dropping ALSA support so you can still watch videos on YouTube, etc. Also isn't something that is installed system-wide, you need to explicitly call something through it.