Travolta is too young for his role

Yes, Travolta was 44-45 in this film and was somewhat too young to be a general. Perhaps that was deliberate in order to emphasize the age difference between Travolta's character, and Lt. Colonel Tall played by Nick Nolte who felt bad having been passed over for promotion and so did not mind sacrificing the lives of his men to advance his own career. He told Captain Gaff (John Cusack) that opportunities won't come easily and he had waited 15 years for that War. Gaff looked unconvinced and stupefied.

As I recall, Travolta played a one-star general. David Petraeus was a one-star at age 48. During WW2, James Gavin was a two-star at 37.

During WW2 we had several generals under the age of 40 and a number of others who were under the age of 50.

John Travolta isn't good for any role. Not even a John Travolta biopic.