There are a lot of accusations one could level at Wenger, but he had the right idea about many things too that the fans are clueless about. Iwobi's talent is definitely one of those things. I don't buy the idea that Wenger wasted him or handled his development wrongly. Iwobi is a good player now and he was a good player then. There was always going to be growth pains along the way. Just look at Anthony Martial and Kingsley Coman who are roughly the same age and frequently wish listed. Both have had a couple of tough seasons where they haven't played regularly and didn't perform consistently when they did play. It's part and parcel for young footballers.
Reiss Nelson is 18 and has only started two league games in his life, and people are on his case now too. There seems to be very little patience in football at the moment, not just at Arsenal.