Napoli is the strongest team in serie a at this moment. They still have deadly duo Conte & Lukaku on their side. They have the bigger chance to win the competition again. I don't wanna compare them to their competitors caused by they have better preparation. Meanwhile, their competitors are mostly changing their coach. Logically, they're the most ready club to win another scudetto at this moment. The odds is also in favor them to keep their scudetto for the next season.
Lukaku is not even being considered right now, sure Napoli is still strong, but they are looking to sell off Osimhen for as much as possible and get Nunez instead of him, to replace Lukaku as well. Lukaku scored like 14 goals, in 36 games, that is not really a lot, that is not terrible neither, but that is not what you expect from the player who won the title as a striker.
When a team wins the league, the striker of that team should be scoring more, and they did had a lot of games where they just got a tie because they failed to score and Lukaku was a big part of it too. I hope that they can get someone better, to be fair I do not believe Nunez would be better, Lukaku could play as well as Nunez, they need someone much better than both.