It's less about total cycles and more about 
    scheduling. You don't really want a real-time 
    or low latency thing like sound to get preempted 
    by another process.

This is true, but Windows and Mac prioritize this well at the OS level. I've been using mostly USB sound devices for the last ~15 years including gaming and never any skipping or desync issues. Not sure about Linux, I have not used it as a daily driver.