In the skybox of Skyline you can see hundreds of flying cars zooming around Mindoro in 2558. I disagree with this. I loved the rustic feel of humanity in the previous Halo titles and I loved the use of wheels and modern looking cars.
Besides, the warthog still exists why use it when you can fight with flying cars? I’ve probably over thought this way too much, just annoys me with the inconsistency.