Just like the other examples you mention, this is intrinsically a subjective interpretation. It doesn't matter how "widely" it is viewed like this, it is not an objective truth. And towards the later period it is completely untenable, since Honecker didn't follow Gorbachev, not to mention the final 1989-90 period. Yet the article deals with the whole existence of the state, so for that reason alone it would be wrong. But even for the earlier period it is just POV. It's like putting "Banana republic" in the infobox of Honduras. The infobox is for universally recognized categories. In international law East Germany was a fully recognized sovereign state, so putting "satellite state" there gives a completely false impression, as if it was some dependent state like a colony, protectorate, or trust territory.