I agree with you in predicting that Napoli will score more goals and not concede a single goal. Of course, in that match, I predicted that the score would be 4-0 in favor of Napoli. However, Pisa played very well. Even though they lost, they proved to everyone that they cannot be taken lightly.

Of course, Napoli is truly extraordinary because they have managed to keep winning at the start of this season. However, they are certainly not safe yet because there are still many matches they must play. Of course, even though Pisa lost, they still have great strength because scoring a goal against Napoli is an extraordinary feat. However, there is still plenty of time for Pisa to improve themselves. But certainly, Conte needs to be vigilant because Juventus will definitely aim to bring Napoli down, so Conte needs to devise a good strategy to ensure Napoli's performance remains strong and they can consistently win.
There are several things that can be evaluated even though they have been very good so far, but we can see that their defense is a little shaky when they try to go all out in attack, and this could clearly be a problem if left unchecked.

The fact that the two goals scored by Pisa resulted from player errors, even though the attacks themselves were not particularly lethal, highlights how a fatal mistake can turn the tide.
However, as long as they manage to secure the three points, I think it's still very good for them because, after all, they are currently performing consistently. But if no evaluation is carried out, this could clearly become a problem for the Napoli squad in the end, especially as the schedule gets busier and busier, which could cause them to falter and disrupt the good form they showed at the start of the season.