I don't think "API" is used in the same sense as what you are using it in. The author is talking about not building your business around an API offered by exter

I don't think "API" is used in the same sense as what you are using it in. The author is talking about not building your business around an API offered by external service provider (eg: Google Translate, or Twitter for example) where your business is dependent upon the the external party continuing to offer that API. The article is not about APIs of libraries.