It's by design
If you zoom out as you travel then the camera will auto-adjust as you move around the terrain
Huh. Thank you for the reply. I seem to recollect that when I started playing back in late july, this wasn't a thing and camera-follow was always on, no matter the level of zoom. It's not something I was bothered by untill fairly recently.
Is there no feature in the options, then, to adjust how camera-follow works? If so, what's it called?