If each vehicle knows where it is, then it knows where the other GSX vehicles and the user aircraft so they should be able to at least avoid those collisions.
As explained so many times already on the forum, each vehicle knows only its own position, because if we tried to make each vehicle aware of all the others, we would have to spam the simulator with so many commands, at each frame, that you will then complain about GSX causing stuttering. So, we had to do with checking only at specific times, and having delays.
And, as explained so many times already in the forum, lots of issues of vehicles doing strange turns, can be fixed by changing their starting position on the parking.
In addition to that, trying to do vehicles aware of each other and automatically wait for each other, would introduce a whole new category of problems, like traffic deadlock, especially on the 3rd party aiports, which are usually made with little not no attention to ground vehicle movements (sometimes they miss the vehicle paths entirely),