You've made your point well, if the question remains,"Were the Egyptian Pyramids used as tombs?" But we can tweak that question: "Were the Egyptian Pyramids always used as tombs?" or "Were the Egyptian Pyramids only used as tombs?" and it's not so clear. If one asks, "Were some Egyptian Pyramids never used as tombs?"--one gets all sorts of answers--but you've been through all this before.
You certainly have generated a multi-faceted discussion.
Now I'll just go back to lurk mode.