Actually if you remove agenda, he was good under Arteta. Our entire defence was poor under Emery last season and Luiz was no different. But there was 0 organisation and Luiz isn't exactly the best in those scenarios.Let’s keep talking about off the field stuff because on the field, where it matters, he was absolutely terrible for 90% +, of last season.
With Arteta playing a very solid and defensive system so far, Luiz has been our best defender. If you ignore that horrendous City game I mean. He had some good games for us in that time. Not saying I rate him highly or anything, but just pointing out he could have been much worse. The problem with Luiz is he will make more mistakes in a 4 at the back. And thats a system we are hopefully moving to (eventually).