Arteta's struggles? You can't be serious, he's a millionaire and he's been handed a job coveted by many on a silver platter; in what other line of work can that sort of thing happen to an unexperienced rookie?
And it's his fault too - his hubris led him down this path, and his hubris alone. Should've started small and not taken the shortcuts. Sorry, but I have little sympathy for him.
What you said just isn't logical though. I don't see how anyone can blame Arteta for taking the Arsenal job, whether you like him or think he's the worst manager in the world.
Extrapolate the situation into the real world. You're an 18 year old kid with little experience in your line of work. You get offered a very lucrative job with a historically top 3 company in the country. No-one turns that offer down. It's nothing to do with hubris. It's about self belief and career advancement. We'd all do the same.
If Arteta is a failure he'll get his comeuppance and lose his job. The people who need to be held accountable are the ones who appointed him and have hidden behind him.