I think the reason for the drop in Osimhen’s market value will be because of the issue surrounding his move to Galatasaray and the kind of deal Napoli is offering. I see no other reason for the drop because despite the circumstances around his move he has being performing well for Galatasaray. It is good news that Napoli are finally deciding to reduce his price tag, this will make it easy for interested clubs to make a deal for his services in the summer.
Maybe the reason why his release price dropped I because his contract with Napoli is remaining one year. Napoli wants to cash out on him at the end of this season since failure to do that will make Victor a free agent. If the Nigerian because a free agent, Napoli might end up not getting any profit from his transfer. The Italian side should be blamed for the losses they might incur if he fails to get a new club since they were the ones that messed up Osimhen's transfer to PSG and even the Saudi Professional League.