By default Mac OS would turn off the backlight of the keyboard after a few seconds to save battery. This setting also turns off Touch Bar. I think that in order to do the Touch Bar more useful and also saving battery we could selectively leave enable only a few buttons and hide the rest of them, so only the buttons we consider more important (1 or 2) could be on all the time, and the rest of the buttons in the Touch Bar would be invisible and saving some battery b/c the pixels in that part of the bar would be off.
You can create two presets, one that contains the always-on buttons and one that contains the rest. Then activate these presets using the "Switch To Preset" predefined action.
However the battery savings would be very small unless the hidden buttons were doing some cpu intensive stuff.
Ok I'll review how to do that automatically after a few seconds or with a button, so I can do the switch fast
Yup, I'd recommend a keyboard shortcut or button for now. But maybe a "inactivity" trigger would be a good addition to BTT.