For me this isn't anything to do with Arteta, in my eyes he is a total unknown, there is nothing to suggest he's good or bad.
The way the season is going (given shortened off-season, shortened pre-season, condensed season with more games played in a shorter period of time) it has favoured, SO FAR, managers who play a passive style as opposed to what is considered a progressive style (teams that have adopted a progressive style of football have dominated their domestic and European leagues by winning and/or competed for stuff for a number of years now).
So, what I'm saying if Arteta is supposed to be a "progressive coach" (I have no idea if he is or isn't but the media say he is) then it stands to reason that this season makes him look shit, just as City, Barca are struggling. So, the concept of who is or isn't a dinosaur (a term usually adopted to describe a style of football that's not capable of competing) may be moot for this season, it could be that as the season develops there is a return to this style, or that it disappears and it's not seen again until next season. So if Woolwich stick with him and this scenario plays out (assuming he is a good manager) than the narrative will on him will change again.
My disbelief is how a manager with zero games under his belt has gained such an overwhelmingly positive commentary on the style of his football just because he was Pep's assistant for 2yrs. There are no prior games, and even now after a 1yr in the job no evidence to back up that he's good or bad (yes they are very bad this season but dig into the context there can be some get-out clauses for him as per pressing teams are struggling this season).
But is he a "progressive coach"? There's zero evidence to support this. Is he a passive coach? There's no evidence to support this too! Because of this, it is fair to assume that this is a significant issue, as his team play with no identity and that this strengthens the argument for him not being a particularly good coach is certainly currently the more persuasive commentary.
But it is hugely enjoyable to see those that were so adamant and so decisively advocating him as the future of football management based on nothing other than he's my mate or he's young or he was Pep's assistant. Had Brian Kidd became their coach would these same people have been waxing lyrically in those same terms as Arteta? I doubt that very much.