Yes, I think they played very well against Real Madrid. Especially the Juventus goalkeeper, he deserves the highest score. We have to realize that teams can't always be stable. Another condition is that it's the beginning of the season, I think the coach is experimenting a lot to find the best combination.
Against Man City yes they did perform badly, even if they should have played like when they met Real Madrid the results would have been different. I think this condition will make Juventus think a lot to improve the condition of the players. This is because the transfer season is also still open, so Juventus can still take advantage of it.
Honestly i still give Juventus a negative outlook, the reason is the lack of serious investments, the team is a half-assembled thing that i don't see working. In my opinion the lack of imaginative players, like Federico Chiesa, still weighs heavily, it was a mistake to have given him away.
For now, especially after seeing Juventus' performance in the Club World Cup, Juventus is still very weak to compete in Serie A next season. There are still many things that need to be changed by Igor Tudor, besides that he also has to bring in players who play as defenders and midfielders because currently Juventus' game is very difficult to create opportunities to score goals so with the existing squad I doubt Juventus can compete for the trophy next season.
Indeed, next season Juventus will start a new chapter after last season which was full of turmoil and full of uncertainty. but the club management finally made an important decision by appointing Igor Tudor as permanent coach. Tudor came not only bringing tactics, but also a tough mentality that was once the hallmark of Juventus in the past. But again as you said they still need imaginative players, so they still have the opportunity to bring in some new players. if we talk about Chiesa, Liverpool also doesn't play him often, maybe when he came to Liverpool he was not in good condition maybe still in recovery, we'll see next season whether he is able to adapt to the EPL and succeed with Liverpool.