I think only Chelsea can't maximize his quality because in other EPL teams like Manchester United he played quite well. After that, his future became increasingly unclear because Chelsea seemed reluctant to give him a place in the squad and that didn't make Lukaku give up but his performance with other teams was much brighter.
I am very grateful if Lukaku has a steel mentality like that and wherever he plays he can always present a consistent game. Maybe I don't really care about his speed but what's more important than that is the quality of his finishing which is still maintained until now. From the beginning, Conte and Lukaku's relationship was still maintained even though they were separated for quite a long time and we know every coach only wants to see players he trusts and Lukaku gets more attention than Osimhen.
Each player is different and not all coaches can match the style of a player like Lukaku so it is indeed clear at Chelsea that Lukaku does not fit there.
Lukaku is indeed a player who has characteristics and he has good quality but in the last few seasons his performance has decreased drastically so what Conte is doing now I think is something very dangerous and Conte's excessive trust in Lukaku could be a disaster for Conte in developing the performance of the Napoli team.
For now we cannot conclude anything even though Lukaku's performance in his debut match with Napoli was quite impressive.