I can see merit in this point if you're willing to put your faith in the OA systems. Personally I trust none of them at this point. Run them at a chain link fence, power line, or tree branch with no leaves and you will most likely by crying "fly away" on the forum shortly after
Course lock works fine for me in the way I described. Never tried home lock on DJI. I have yet to be in a situation where I feel it would offer any benefit, same as smart mode on the H.
When the RealSense module is released, I'll be very keen to test it out. Maybe it can achieve the vision resolution needed to reliably navigate. I did see in a recent demo video that the H equipped with RealSense will yaw automatically to keep the vision system facing forward. Currently my H isn't smart enough to do that when in follow me mode.