Competition certainly sounds nice on paper, but think of the problems that the various sound servers/api's have caused. OSS(+ 4Front's version), ALSA, PulseAudio, Jack.
ALSA is monstrous to configure, but capable.
JACK serves a very specific purpose for music production.
I'm still not sure what pulseaudio is for, but I don't think I'm the target audience for it.
Point is, they don't exist contrary to each other, but in parallel and often in concert.