"it still provided a modern sound experience. We could enjoy sounds from various and simultaneous sources at the same time, an unheard of luxury at that point. At the start of the project the promise was low latency sound at the same level of flexibility as on both Windows and Macos. "
Those are all things that the OSS driver did natively in the kernel on other systems for years. FreeBSD had all of that - no need for some kludgy userspace addon.
Any sane advancement for Linux at that point would have been to fix your crippled OSS implementation, not add workaround hacks, or new feature-incomplete drivers like ALSA.
"With systemd its seems like a major headache setting up your desktop in a way that you can play music in your speakers, while you are fixing yourself a nice cup of drink."
I didn't know this, but it demonstrates the issue perfectly. What the hell is systemd doing messing around with your audio?