both Sky and BT invested a lot of money in being able to resolve copper faults so have a good capability to both identify what's needed and get appropriate action from Openreach, I don't think anyone else does.

Bullshit.

I had Zen, and we had identified exactly what the issue was quite quickly.

the Openreach infrastructure really is separately managed. BT Consumer is just another ISP now.

Then split it off. BT cannot be trusted to be impartial, regardless of how many "former BT employees" tell us otherwise.