There was a compass error and the aircraft was going through TBE? ( most people on here wouldn't have a clue or the skills to counter it).
If your aircraft had thrown a prop and was spinning out of control?
If the IMU had failed and stabilization was compromised?
If the aircraft entered Atti under Gusty conditions and the pilot was inexperienced in controlling a non GPS stabilized aircraft?
All nice hypothetical scenarios which happen how often?
And last for how long?
In over five years on these forums, I've heard the suggestion many times but never seen a report of anyone using CSC to stop one of those situations.
A compass error doesn't cause the drone to hurtle away, out of control.
Hands off and it hovers there doing slow, lazy spirals.
Thrown a prop? .. That drone is already on its way down toward the ground. CSC isn't going to do much to help.
IMU issues? I had that once myself. The drone could climb or descend - just not fly straight.
There was no need to CSC to get it to the ground quickly.
Unexpected Atti mode? That could happen (rarely) but hands off and the drone slows and you've always got the ability to climb or descend.
Unexpected emergencies are rare and usually don't last very long.
The flyer initially uses their time trying to sort out the problem and by the time they work out there is no other way but to pull the CSC pin, its too late anyway. The drone is already on the ground or a wall or a tree.
The emergency CSC to prevent a catastrophic tragedy is an exciting hypothetical but rarely (if ever) happens.
all you need is the RC link, which as you know has nothing to do with the navigation going bonkers and resulting in an uncontrollable craft.
Sorry, I'm not following.
If you have the RC connection, you can steer or climb away from trouble.
If you have lost connection, you can't CSC anyway.