[twright0]

This doesn't seem accurate - the scenario needs to be imaginable, but that doesn't mean it's a prediction by the author. I could write a story about the downstream effects of discovering FTL travel in 2030, but that doesn't mean I think it's going to happen. Even for something more realistic - something that will probably happen on some timeline, just not right away, like a Mars colony - the author might not want to explore or think about other technological or societal changes that happen in a longer period of time? Fiction is just that, fiction

[Aeolun]

I’m going to use VR worlds as a major plot point, and I vaguely intuit that will be likely around the year 2035, why would I set my story in 2100?

That would require me to deliberately adjust my timeline to make “predictions” less likely.