That video and the results are astounding. And, circling back to your point about where to use the PID: I think that perhaps we need to split things more finel

That video and the results are astounding. And, circling back to your point about where to use the PID: I think that perhaps we need to split things more finely: The fancy part of that video was WRT overall flight trajectory planning. (See also your obstacle avoidance descriptor). You might still use PID for the angular rate control (or not), while feeding those target rates from a higher-level algorithm that commands attitudes, flight paths etc. (Or flight path -> attitude -> angular rates etc) I went down a rabbit whole of constant angular jerk and time-to-correct targets for a while, but wasn't able to get it working. So, there are multiple layers involved for something like in the video. A properly-tuned PID works well for manual angular-rate controls, and autopilot commands that reduce down to angular-rate controls. But PID tuning can be tricky; and/or can be done automatically; or replaced with something more sophisticated.