If you took Arteta and Arsenal out of the consideration and just looked at the league results and table, most would agree the manager of a team in such a prolonged run of form must go. Arteta might turn out to be great manager eventually but right now he's leading Arsenal down a dangerous road.
The problem with Arteta is that he has no track record to speak of, so we have no idea if he has it in him to not only turn it around but to be an actual good manager at this level in a general. That's the risk we all took when we hired former players who are complete rookies. Arsenal is a mess from top to bottom though, and it's hard to completely fault Arteta but he has made some utterly bizarre decisions that, imo, are huge red flags anyway.