I believe the other reason he appears to be very important for the team is that he has no competition in his position - I initially thought Boniface was going to be that guy to give Osimhen a tough challenge for the 9 spot, but he ended up being the biggest flop, hooked and dumped out of the National team.
Until we have real competition in that position, we will be overly reliant on Osimhen, and he has shown on multiple occasions that we cannot cope without him. He improved the squad when he is on the pitch.
Before now, the Super Eagles used to have more than one key player. When we had players like Emmanuel Amunike, Finidi George, Daniel Amokachi, Rashidi Yekini and so on in a team. All these players were dangerous up front. In the last Nations Cup, Ademola Lookman, Moses Simeon and a few others were exceptional. Now, from our few games, without Victor Osimhen, everything goes deem. Tolu Arokodare became the worst attacker that I still prefer Victor Boniface.