The Timeline Deception - Did the Millennial Reign already happen?

Was "Tartaria" really the Millennial Reign of Christ?

The architecture could not have been created by mere mortals. And where did the knowledge of this technology go? For that matter, where did all the people go, who needed such huge structures? Back to heaven, with Christ?

https://www.youtube.com/watch?v=KVeYMDLKbfI