With the use of sprint and thruster pack, it is very easy to match the speed of a fast-moving vehicle, allowing you to board it with ease. Because of this, the range from which you can board vehicles does not need to be as great as it is.
Here are two examples of what I’m talking about.
Being boarded in a Banshee from twelve feet away while rolling:
Being boarded in a speeding Warthog:
This turns vehicles into utter laughingstocks when going up against anyone who has the slightest idea of how to use their thrusters to hijack.