Suppose a civilization discovered the technology of a craft capable of near relativistic speed. Suppose they did this 100 or 1000 million years ago. All they need do is park their craft near a black hole and allow time to race past them while they reamined in a slow orbit near a black hole horizon. They leave orbit after a year and ZOOM the rest of the universe is a million or more years into the future.

My point is...

The craft we see could be from an extreme antiquity while they seem quite futuristic to us.