For one thing, Chinese government does have an incentive to enforce good encryption so that foreign adversaries cannot snoop in on important Chinese communications. Only the Chinese government has access via Tencent’s backend.
First off the Dutch are pretty important for a few reasons, their ports and cyber program being the first things that pop into my head. As for Wechat, why wouldn't Chinese officials use it? Even if they didn't use it for official work (which they do, to the best of my knowledge), just about everyone there uses it.
