The Tomorrow War and the value of advance warning

What is Senica's main objection to The Tomorrow War?

He thinks advance warning and future technology should be used to prepare for the invasion before it begins.

Senica objects to sending people forward in time to fight an invasion that the present now knows is coming. He would use that warning to prepare beforehand. Bringing future technology back provides a second advantage in his alternative. The criticism treats warning time and preparation as resources, while leaving the film's time-travel constraints unexamined.