Act5: Did true love or immaturity play the more significant rols in the events of the Tragedy of Romeo and Juliet?

I would say that immaturity played a greater role in their tragedy. I think impulsive love combined with a disregard for the consequences of their actions are tragic flaws for both these characters. Shakespeare had the adolescent brain figured out in the 1600's. It would seem not much has changed. Adolescents are still prone to take impulsive risks today.