Personally I would consider Inter milan as the strongest squad in Serie a. Napoli's squad is not weak. However, their attack is still quite weak. Last season we saw inconsistent performances from napoli's attacking players. And this season too, the team has not bought any experienced strikers. However, it is certain that Napoli and Inter Milan will fight for the title. Teams like Juventus and Roma do not seem to be able to perform well consistently. On the other hand , AC milan lost their first match. Expectations cannot be high from this team either.
You mean Inter Milan are the best team in the Serie A this season or all time? Imo, they're not as good as they were 2-3 seasons back and if you are comparing the striking force of Napoli to that of Inter, the Nerrazurri can't come close. Have you seen what the likes of Marcus Thuram and even Lautaro Martinez are doing now? Don't get me wrong, Martinez is a good player but he's not as reliable and good as he was before and even Thuram, since he got back from his injury, he has become a shadow of himself.
Look at Napoli, there's just not a lack of good players. When Romelu Lukaku can't perform, there's Scott Mctominay stepping up. Like there are good players in Napoli who would ensure that this season ends with them being the champions.