While infact, Arsenal have not managed to advance to the UCL final this season, Arteta has once again failed to bring his club to lift the trophy, for the umpteenth time. Arsenal Lost to PSg with aggregate 3 - 1.
Arsenal are just being themselves. Giving their fans a silver lining in a tournament and failing them again and again... 
I don't know what's going wrong with them when they get close to a trophy honestly. The same thing happens in the Premier League and now the Champions League too.
They have a beautiful squad. Arteta is actually not a bad manager. Arsenal were much worse before he came. Maybe completing the last piece of the puzzle (a reliable CF) might be the key?
Arsenal's squad is strong. Arteta is also a very experienced coach. Even then, the team is not able to win the Premier League title. To win the Premier League title, it is necessary to play consistently well. But Arsenal has failed to do this.
Arsenal has been competing for the title in the last few seasons and has been in second place in the table until the end of the season. Every season, we have seen that Arsenal's performance becomes unstable when an important player in the Arsenal squad gets injured. Arsenal has a strong squad. However, Arteta does not have a suitable replacement for the players in the squad. If Arsenal does not add more talented players to their squad, it will not be possible for this team to win the title.