Something that was very prevalent in the prequel trilogy was foreshadowing. Many things show a sort of evolution into the original trilogy. One that makes perfect sense is the portrayal of the Old Republic. Given that we see the Republic becomes the Galactic Empire in Revenge of the Sith, it makes sense that the Republic has many similarities to the Empire:
To name a few:
- Clone Troopers look like Stormtroopers
- Jedi Starfighters look like Star Destroyers
- Jedi Interceptors and V-Wings look like Tie Fighters
- Both the Republic and the Empire used walkers and Star Destroyers
It's obvious that the Republic becomes the Empire. There is, however, one ship that not only breaks this pattern, it goes in the complete opposite direction - the ARC-170 Starfighter. Instead of resembling something the Empire would eventually use, this Republic fighter closely resembles something the Rebellion would eventually use - the X-Wing Starfighter.
Both starfighters have:
- a long and thin nose/fuseloge
- large cylindrical engines placed between the fuseloge and the wings thin horizontal wings
- long blaster cannons at the ends
- s-foils that open to form a sort of x-shape
- both have the red and grey/white color scheme
I mean, it is as if the filmmakers were trying to imply that the ARC-170 starfighter is some sort of predecessor of the rebel x-wing fighter, which seems to go against the Republic's trend of having things that evolve into Imperial things.
TL;DR: Why was the ARC-170 starfighter made to resemble the x-wing? Have the filmmakers commented on the decision? Is there some sort of backstory/retcon to explain why a rebel fighter would look like a descendent of the Republic/Imperial fighter?