Arsenal were in a really bad situation when Arteta took over. They were not playing legendary football like in previous years. Despite this, it managed to become very successful in a short time and now appears as one of the biggest teams in Europe again.
There is a similar situation in Chelsea, actually the situation of the team is not so bad but they cannot achieve success. Towards the end of the season, their performance increased significantly and they started not making mistakes. Maybe they'll manage to continue like this next year
Arsenal current revival is of course inseparable from Arteta ability to build a solid squad by relying on young and senior players, Arteta has done a good job at Arsenal after previously Unai Emery failed to bring Arsenal to become a challenger for the Premier League title, Arsenal performance has improved dramatically when the current Arsenal management began to support Arteta by bringing in the players they have needed all this time to be a challenger the Premier League title, Arteta experience and ability as a former Arsenal player make him better understand the philosophy that Arsenal has been carrying, in addition to the coaching knowledge that Arteta got when he was Guardiola assistant.
Arsenal have now started to return in the right direction and of course they hope to be able to restore the glory of the Invincibles squad as in the past, but compared to Arsenal today, of course Chelsea problems are more complex in my opinion, so far Arsenal is a team that is more inclined to rely on the process and is different from Chelsea who currently hope for instant success they get, So it does make the current Chelsea coach job very difficult to make it happen.