Why did the dutch replace the portuguese as the main european imperial power in asia?

They captured Malacca from the Portuguese and opened trade with China. They used military force and forged close ties with local rulers than the Portuguese had.

Explanation:

Some hostilities commenced in East and Southeast Asia in1511 between the foreign sea powers in when the Malacca was taken over by people from Portugal who controlled the access to the seas and trade in that area. Verenigde Oostindische Compagnie (VOC) a Dutch East India Company, devised means of destroying the Portuguese stronghold in that area.  

In 1605, VOC got permission from the queen in that area in order to launch an attack at the Santo Antonio. The Dutch built their company by the permission of the queen and seized the ship of the Portuguese because the relationship the Portuguese had with the Pattanni in Malacca has broken down.  

( sorry my answer is short they wont let me do just war so ignore this) xd

b, the anti immigrant fervor