Napoli's effort to prevent other teams from taking Osimhen is the main reason napoli put a very high price for him. But, time flies and the situation changes. Osimhe's performance has dropped drastically, and it was also affecting his price too. So, i see no reason for napoli keep him much longer.
The deal between Chelsea and Napoli will likely happen soon. This is because these clubs have talked a lot about the deal for Lukaku and Osimhen. The swap is most likely to happen soon, and for the last, let's see how much the new asking price offered by napoli for osimhen.
I don't know why many of us say that Osimhen has experienced a decline in performance in the last few seasons, because in fact we can see that his performance is quite stable with Napoli even though his number of goals fluctuates with Napoli, but although he is still able to make a lot of contributions to Napoli wins and games so far, actually Napoli don't have a strong reason to keep him in the squad considering Conte desire to bring Lukaku from Chelsea, but it wouldn't be Napoli if they didn't want to get a lot of profit from selling their players so far, so far we know Napoli as a club that often sells its stars, so I think as long as there is a team that is willing to offer a high price for their player of course de Laurentiis will not hesitate to let go of his star players.
Previously, Chelsea had tried to recruit Osimhen from Napoli and Napoli asked Chelsea to exchange players between Lukaku and Osimhen but Chelsea refused, currently Chelsea has recruited many young and expensive players so I think Chelsea will not try to recruit Osimhen again in order to avoid financial violations happen, so it is very likely that if Napoli sell him at a slightly cheaper price of course another club might be Osimhen destination.