Arsenal has a good chance to compete for the Champions League but they are not on the list to win it or reach the finals. I suggest they should focus mainly on winning the Premier League which will enhance their chances of winning the Champion League anytime soon. Arsenal are likely favoured to win the Premier League this season if only they would enhance their performance since Manchester City is a better contestant for the Champions League, for what I know they will try as much to devote more effort into UCL other than the Premier League which gives Arsenal a bolder step to accumulate more points than City.
Expectations for Arsenal last season in the Champions League were actually quite good, especially when they performed consistently in the Premier League, to the point where many predicted they could get rid of Bayern Munich in the quarter finals. In fact, Arsenal ended the season empty handed, without a single trophy in their cupboard. This failure was very disappointing for fans, because Arteta had built a very good squad with a number of expensive players in his squad. Next season, if Arsenal perform consistently in the Premier League, it is likely that they will perform with the same performance in the Champions League, but Arteta would be better off prioritizing winning the Premier League trophy first. Because theoretically, the competition in the Premier League is more capable of being controlled by Arsenal than the Champions League, even though the number of matches is much different.
I actually didn't have high expectations for Arsenal's performance in the Champions League last season, even though they performed well in the Premier League, but that doesn't guarantee that they will be able to beat Bayern Munich. In fact, Bayern Munich is a club that has a lot of experience in the Champions League because it has become a regular at playing in the Champions League, whereas Arsenal has less experience than Bayern Munich so it is very clear that a club with experience is superior in terms of mentality and performance.
So don't exaggerate too much about Arsenal in the Champions League, but in the Premier League I still fully support Arsenal being able to win the title there in the last 2 seasons. Arsenal almost got it with only a small difference in points with Manchester City. Hopefully Mikel Arteta doesn't give up on improving the club's performance be even better next season.