I agree with you. Even though this season's results are better than last season and they also qualified for the Champions League next season, overall I see that Juventus has not experienced a significant improvement in performance. Results are better this season as Juventus only got 5 defeats with 2 games remaining. But they also did not get a significant number of wins. Most of them are draws. This must be an evaluation for management or coaches because next season they will play in the most competitive league in Europe.
You are very right in the sense that it's true that there have been no actual significant improvement in the performance of Juventus they are only trying to maintain a form and some how it feels like they are still at their build up stage and are even getting to make a better form probably which we are going to see them putting up by next season when we could say they have had a complete improvement already but then they were still able to achieve a few things this season.
Getting to qualify for the champions league which they weren't able to do last season is actually such that could be considered an achievement although it's looking much like it's something they should be able to do since they are been considered an elite team I'm their league so getting to qualify for the champions league is more like a normal achievement they should get and if we consider their start this season we would accept the fact that not getting to qualify for the champions league would habe been very embarrassing because they had earlier been in the title race.
The kind of dorm Juventus did portrayed this season if they should get to play in the champions league with such form I doubt if they will be able to make it beyond the knock out stage considering the new rules for the champions league which seem like it's going to be much longer and stressful than that which has been the regular before the effecting of the changes in the champions league.