Well, I was a flight instructor for many years and flying a plane is super easy too. For me, but for someone who never did it before, it would be extremely difficult, to impossible. I'm someone who never did anything to a drone before, other than changed props and a battery. Therefore, just the thought of attacking a gimbal would be enough to frighten me.
I wish you had been my neighbor, then I could have dropped round to you, to show me how easy it was. All in all though, it was a good deal in the end, what DJI charged me to get a new drone. I have read where others, who also thought it easy enough to change out their who gimbal and camera, had continued issues after they did the work.
As I mentioned, I had a repair place do the work first and had to send it back twice because they could not even repair it properly. Then they said they would refund me, but despite texts afterwards asking for the refund, they never responded back, so I would never suggest anyone use them, they don't live up to their word.
I appreciate your thoughts though, on how easy it could have been. For my situation, I should have sent it to DJI in the first place. I would not have a clue where to begin if I tried to do the repair, even if someone on YouTube were showing me.