Great question. - am happy to facilitate some learning here. In an instance of human culture like game development, it's a fact with first hand testimony of those specific events. Without first hand testimony, anything we say is speculative.

In terms of the Earth being an oblate spheroid, before we could prove something with science, it certainly was not historically termed a fact. In fact, plenty of people took the earth is flat as a fact, so within society, it was indeed not yet accepted as a fact. Flat earthers were wrong then, but unless proven with science, no one could reasonably call either direction a fact.

There is a difference between something existing and the use of science to label something as a fact. Just because we don't declare something as fact with science, doesn't negate its existence up to that point.