I think the issue is very Simple
Global Warming will sink this island in 10-30 years , so strategically China and Japan need not to worry about this small island
what they should do is sit down on table , and agree to build a big Drinking Stand in Island Owned by UN.
When the Island will go down it will go down , under water why waste resources and increase tension over something that will sink under water anyways
Complete waste of time
Its a not a good island just few trees growing and no space to build anything ....
I think Chinese officials and Japanese should sit down , and discuss and say on we will take half of the trees on Island and you will take half and after that we will had over the Island to UN , and consider it deserted island
This land will be 100% under water in next 10-30 years , and there is no value
But its logically belongs to China since its closer to China and Tiwan , not sure why Japan wants it they should focus on their problem with Russia