Been there, seen that. Architecturally, it is nothing special, I would say T5 was more impressive. Yes, it has a clean fresh feel to it, but so does T5.

I'm not sure of the value of comparing an airport terminal on a bad day with another airport terminal on a good day.

As for losing pax, you can't stop people thinking what they want. I should be slow to make significant purchasing decisions on the basis of teething problems. Others may be more impetuous.