alt Hacker NewsI don't necessarily use the numbered function keys all the time (as in F1-F12), but I use those physical buttons constantly. Brightness, volume, play/pause, mic mute, are all buttons I press a good bit. Many of those I'd rather just have be a single quick button, especially things like speaker or mic mute.
Volume and brightness are exactly the place the touchbar shines: tap and start dragging and you're adjusting a slider, which is much better than mashing a button.