I believe Juventus will be able to improve their performance much more by the coming season. They started to perform better especially after they signed Vlahovic. He made their attacking line stronger than before.
Too early to judge they will improve their performance. The problem in Juventus isn't only about the attacking line, but they also have problems in both midfield and defend lines. So, the problem is quite complicated. Another problem, the players have no good mentality as the winning team anymore. The coach must fix this if Juventus wants to improve their performance in the next season.