I don't think there's any way Apple will dilute the brand of one of their flagship products in their hottest market. Plus, it works both ways: they would have to find a trademark that works everywhere else so that competitors don't snatch up the new trademark in other countries.
If I need to I could come up with $10,000 for something. That doesn't mean that it's not significant and it doesn't mean that it's the right thing to do if I have an alternative.
* Cost of finding and registering a different trademark that's available worldwide.
* Cost of developing new marketing materials.
* Cost of tweaking software to use new name.
* Cost of tweaking production lines to print new name on devices and packaging.
* Cost of lost sales due to customer confusion (Chinese traveling to America; Foreigners traveling to China).
What I'm saying is that $1.6bn is clearly not nothing, not to Apple, not to anyone.