I also think that Napoli will still be very similar to last season, even though there will be slight changes at Napoli, it will definitely not be so bad for Napoli because they will still be one of the strong candidates in Serie A next season. Although I also agree more with what you said because before the season starts speculation for the Napoli team sometimes wouldn't be more accurate to say, so it will be better to see how Napoli do at the start of next season in the league.
If Napoli don't get a replacement that is commensurate with Kim Min Jae, then there is no guarantee that Napoli will be balanced next season. Especially when I think the departure of coach Luciano Spalletti will have a huge impact on the Napoli squad. So far Konstantinos Mavropanos defender belonging to VFB Stuttgart is being linked with Napoli, he has played for Arsenal but is not showing a good trend there.
Napoli move will be really difficult to defend the Scudetto and go further in the European Champions League if Khvicha Kvaratskhelia and Osimhen leave in the transfer market this time. It takes several seasons to build a squad like Spalletti did, hopefully Rudi Garcia can bring Napoli to success in the future.