Perhaps it was just me...
Okay, I've found two ways around this problem:
1. It turns out there is an actual physical 'home' button on the dash. Pushing that is much easier than reaching for the tiny AA exit button, and then fiddling with the 'return to Chevrolet' menu bar on the touchscreen.
2. The 'Return to Chevrolet' bar does seem to work properly
IF I first press either on the blue arrow icon at the left part of the bar, or on the blank space toward the right side of the bar. But if I press anywhere on the actual words in the middle - Return to Chevrolet - the touchscreen does NOT return me to the home screen, and not only that, it freezes the on-screen Return to Chevrolet bar so that even pressing the blue icon or the blank space will not work (I then need to go back into any AA function and try exiting again, or just use the physical home button).
I am ok with my workarounds, but I would like to know if I have a touchscreen defect I should get looked at by my dealer (or if we all have that defect in software). If you have a Bolt and an android handy, I would appreciate your checking that Return to Chevrolet onscreen menu item, and letting me know if yours has the same glitch as mine when you touch it directly on the words. Thanks!