Yes she was closed to dialogue for now. But we don't know what other ways Twilight could have changed that.Right then Starlight was full of anger. Highly emotional. Full in a battle mindset.Like I said, It could have been that after a while of these loops Starlight would have calmed down enough to be spoken to. Or Twilight could have found some other way of getting her to speak. We only saw the one way it happened.And yeah, again I'll admit that it IS possible that the way we saw was the only way. But we don't know that for certainty.Starlight saying those lines like "all of eternity" is exactly the kind of irrational thought I would expect someone who's highly emotional and upset to say. And eventually they would calm down. We've seen that Starlight isn't always in such a sate. So it feels unlikely that she would remain so for the rest of time.Though I am admitting that it is an uncertainty. We don't know what effects the looping can have on her emotional charge, If it keeps resetting her adrenaline or not etc.And that's really the only part I'm challenging in your statement. That seeing that future was the only way to reach out to her.