Let's not judge by the first rounds. Juventus has enough time to improve the situation in the domestic championship.
The last season is the first one Juventus lost Scudetto after many years. In previous seasons, they sometimes have bad starts but at the ends they won Scudetto. I agree that we should not under estimate the strength of Juventus.
I don't think Juventus has enough time before the end of the transfer window to make important acquisitions in the defensive and offensive lines on the flag, so Allegri will have to make do with the material that is available at the moment.
Allegri needs time to work with players and brings Juventus back to where they were in last one decade. Juventus will dominate Serie A again, if not in this season, it would be in next season.
On the one hand, the club's management seemed to have foreseen the consequences of the decision not to renew the contract with Ronaldo after next season, but it turns out that the club was not 100% ready for the situation to unfold at such a speed. However, excluding the situation with Ronaldo on other lines, the composition was considered quite good before the start of the championship.
I agree that the transfer of Ronaldo at very end of transfer season causes trouble for Juventus. They don't have enough time to buy other striker to replace Ronaldo. I think Juventus will have to find strikers in Serie A in the last days of transfer season. If they can not find any striker, their strength will be affected.