It's not spooky at all when you understand the psychology behind horoscope predictions and so on. As long as any random prediction stays vague enough to be applicable to many different situations and as long as about 60 to 80% of what's predicted cóuld indeed happen theoretically with a somewhat high likeliness, it will eventually sound familiar at some point or will seem to be talking about a certain specific event... As a reaction (some) people believe it did predict something.

Truth is, it did not predict anything, we ourselves have just found an event that matches the words.

It only would become spooky (and believable) by the time a prediction is extremely and almost overly specific about what's to come, giving the exact date, time, names and so on,

Cheers