I think there's no doubt we would have received a better fee for Guendouzi if we hadn't been airing our dirty laundry in public. He's become a tainted asset now. The way he's been ostracized might well be because of an underlying issue with Arteta when it comes to young players who don't behave impeccably too; I'd say it's even likely, and generally I think that will end up hurting us more than it's helping.
Having said all that though, sometimes you just need to put your foot down. My biggest gripe with Guendouzi is that, in addition to working up a pretty extensive track record at such a young age, he's also a bullshit footballer. And I don't mean that in the sense that he lacks talent, but he absolutely lacks brains, and I reckon it's mirrored in his impulsive personality.
He's genuinely one of the slowest and least aware players I've ever seen on the turn, which is a bit unfortunate when you're playing a position where it's literally your job to turn and move the ball between two banks of players while being aware of your surroundings. These are not things you're supposed to struggle with if you make it to this level. The fact that he does implies that he doesn't have the necessary drive to improve. They are so basic that there's no way someone hasn't tried to teach him. He just lacks the application, and the ability to take on advice. It's why he loves someone like Emery, who is notorious for being soft on troublemakers and gave him plenty of chances despite his flaws, and consequently struggles to function with everyone else.
I will be pleased to see the back of him, and if there was one thing about Arsenal that I could undo from the past few years, putting so many minutes into his development would be high on my list. We've produced plenty of academy players who would have been better served by being given those minutes. Maybe he'll wake up one day and start taking things seriously, but I don't want to wait for years to find out. Maybe he actually has a strong case of undiagnosed ADHD, in which case I'd be more sympathetic, but it would also make me want to keep him even less.