Total lack of consideration of Einstein's theory of relativity
https://www.youtube.com/watch?v=iSyfpUyzQGU
If these starships were capable of going several times the speed of light, then where is the factoring in of Einstein's theory of relativity where time will slow down on the ships but outside everything else goes in normal time...this would result in rapid aging for everyone outside the ship, so a starship that goes warp factor 8 for a significant period of time and then comes back to earth, everyone on earth is either significantly older or dead.