Duterte can't do anything, because the Chinese will simply stop exports from the Philippines and destroy the economy. There are also many other ways they can turn the screws, including possibly turning off the country's power grid.What Filipinos think of China & The South China Sea Dispute | ASIAN BOSS
The average Filipino was frustrated with their president's seemingly defeatist approach to dealing with China, a year ago. But what could he do, with the U.S. bases there closed, and his own nation having a small and obsolete navy and air force? Since then, things have supposedly changed, due to plans to rebuild half of Subic Bay for the U.S. Navy, and even have a warship-building infrastructure there.
I do understand the desire to be neutral, but that won't work due to China's behavior. The Philippines is one of many nations caught between the cold war between the U.S. and China.
By the way, I've posted this map before, but the Vietnamese number is really interesting to me now. They border China, they were once part of China for centuries, they are the most culturally and ethnically similar to China (other than Singapore, obviously), and yet they have not allowed the Chinese to get a hold on their economy. It's almost like they know something the other countries don't.
It's also worth noting that the lower a country's percentage, the more antagonistic they are to China.