I don't really understand what the language spoken in a country has to do with the trade industry but I sure don't see why we shouldn't trade more with Holland as long as it's beneficial to both Holland and for our country. As long as there is good money to be made we absolutely should trade with whatever country needs us as much as we need them.
It's interesting that more Dutch people speak English than Canadians, but I don't think that's a reason to trade more with them. Trading is about resources, not shared language. That's why we have translators. I don't see any correlation between the Dutch people speaking English and pursuing more trade with Holland.
It's silly to base trade on language alone. Most other countries encourage their business people to learn English, more than we do to learn other languages. Yes, if Holland is producing items we need, and willing to consume items we sell then we should trade more with them. However there's no reason to stop trade with Canada, and trade decisions should be based on economics, not linguistics.
No, it makes no difference what the English-speaking population of another country is. We trade with other countries for economic reasons and to ensure that there are enough affordable goods to go around. What language is spoken in the nations that trade with each other should have no impact whatsoever on how much trade is done.