Arsenal did try their luck and managed to become top of the standings, but I agree that they won't be first until the end of the season... Last season they had a 100% opportunity to win but god only knows why they couldn't do it... This season it seems to me that history will quickly repeat itself...
Last season, their sole aim was to qualify for the Champions League Football and that they achieved. Anyways, they should have done better by trying to win the league. The draw against Southampton was painful that should have given em a clearer pathway. They snoozed, they failed and I believe lessons from the experience has been learnt.
Manchester City didn't replace some of them players well though, it has affected their general performance. I also do not see Manchester City as winners of the Premier League Competition.
There should be more additional players that fits into the plans of Mikel Arteta long term plans for the club. Arsenal was my favorite to win last season, I'm still rooting for another club to win. Pep Guardiola gradually turning the league into farmers league LoL.
The only reasons why Arsenal failed last season were the lack of rotation options, unbalanced squad depth, and Arteta tactics which seemed easy to guess. Of course experience is the best teacher and Arteta has learned from the bitterness of last season, his efforts to improve the club by recruiting like players Declan Rice and Kai Havertz, and changing several approaches in his strategy made his squad successful in defeating Man City, for me this success shows that they are very ready for any challenge this season.
I don't doubt Pep Guardiola in managing his club, I think even though some of their new recruits are not optimal, City is still on the favorite path as a champion candidate. City defeat to Wolves and Arsenal does not necessarily put them off the list of favorites, I mean last season we saw them still win the EPL trophy with 5 defeats and 5 draws.
Apart from that, I think many things will happen in the next 24 matches, it could be Liverpool becoming champions at the end of the season, or it could also be Arsenal, and it doesn't even rule out the possibility that City can defend it again. The competition for the top four continues with a narrow points gap, a slight gap will result in their position being displaced on the standings.