It appears William and Kate were not subjected to the usual Norwich security gestapo or indeed the £10 departure fee.
They were driven through a security gate to the ramp and boarded last minute avoiding the plebs.
As for my critics the airport scores 3/10 on Skytrax and here is a review from this month.
sleepy, lazy and incompetently-run airport"
M Warden (United Kingdom) 7th August 2019
✅
Trip Verified | A sleepy, lazy and incompetently-run airport - with an outrageous £10 "airport improvement" tax. OK, Norwich airport does have some advantages: it is small, and it's possible to park 20m from the main entrance. But that's about it. Check-in staff were fine, but then all passengers have to pay £10 for a ridiculous "Airport Improvement" fee. It's just rent-seeking by a lazy management team - no sign of any improvement since I last travelled through Norwich airport 10 years ago. And then security were unable to scan phone-based boarding passes. In an airport. The lack of urgency or interest in giving customer service from the security screening staff was about as poor as I've seen anywhere in the world. Just shameful. The Business lounge was equally laughable. There was tea, coffee, a couple of soft drinks and a few bits and pieces of snacks. And that was it. OK, it's a small airport but clearly they do the absolute minimum consistent with having a lounge for Business-class travellers. Barely worth being in. Arrivals experience was a bit better - the plane had to wait 15 minutes for ground staff to bring up some steps, which was poor. But passport control took seconds, and bag delivery was only about 10 mins. Still, I would avoid flying out of Norwich if there's a sensible choice to go elsewhere.