Minkowski spacetime is primarily concerned with causal distance; whether event A can be causally related to event B. Time has a negative sign when you’re considering causality, because your primary goal is to see whether any effect from event A could have been involved in event B. Using the Minkowski definition of time, an object A ten million light years away from object B has a negligible spacetime distance from that object ten million years in the future and ten million years in the past from any given point in time.
Minkowski spacetime is primarily concerned with causal distance; whether event A can be causally related to event B. Time has a negative sign when you’re considering causality, because your primary goal is to see whether any effect from event A could have been involved in event B. Using the Minkowski definition of time, an object A ten million light years away from object B has a negligible spacetime distance from that object ten million years in the future and ten million years in the past from any given point in time.