Yes, disabling sound mixing will prevent multiple applications from using the sound card at once, in much the same way as disabling graphics drivers will prevent X11 from working.
X11 never came with graphics drivers disabled by default.
aRts is for pre-ALSA (ie OSS) applications.
aRts isn't "for" ALSA or OSS applications; in fact it doesn't play nice with either. aRts is for aRts applications. aRts has backends for both OSS and ALSA.
There's no reason glitch-free playback and per-application volume control can't be done in the kernel. The only feature that makes sense to do in user space is network transparency, which is of limited utility.
X11 never came with graphics drivers disabled by default.
aRts is for pre-ALSA (ie OSS) applications.
aRts isn't "for" ALSA or OSS applications; in fact it doesn't play nice with either. aRts is for aRts applications. aRts has backends for both OSS and ALSA.
There's no reason glitch-free playback and per-application volume control can't be done in the kernel. The only feature that makes sense to do in user space is network transparency, which is of limited utility.