Though Rudi Garcia has been unable to replicate the same feat his predecessor achieved last season, I think it'll be too early to show him the exit door from the being Napoli's manager. The French professional football manager took over the managerial role at Napoli after the club's former manager Luciano Spalletti left the club few days after winning the Italian Serie A title for the club. Rudi Garcia I think isn't a terrible manager and deserves to be given more time at the club to prove himself.
The new season is just past three months and there's every possiblity that Garcia's Napoli might come back to winning ways again.
Rudi Garcia has had quite a lot of time since the start of the season, many matches have been played and Rudi Garcia should also have gained insight from several of these matches to find the right way to improve the performance of Napoli players.
I respect your opinion but for me it seems like Rudi Garcia is a little unsuitable at Napoli but I will wait for the final results of this season and see if the coach is able to give Napoli a title.