dogs learn how to behave towards people and individuals by observing their behavior towards them. They avoid to live conflicts with people by moving away from them and they do not move towards them.
Different individuals behave differently, different groups behave differently, their actions towards people are affected by their experiences with people, so I did not find anything that suggest stray dogs behave aggressively towards people. Stray dog behavior cannot be generalized. Each incident should be investigated individually.