My friend it didn't change life of all the people as this world is not perfect and it did not implements teaching of islam as per its assence,,, If you want to see example how real islam totally eliminate caste and treat equally all humans from social aspect then go and read history of reign of Muhammad (SAW), Abu Bakar (RA), Umar (RA), in their government no one superior to other based on caste or any other unjust criteria,,,
We muslims did not implement real teachings of Islams,, its our fault not the fault of Islam itself,,, just read last surmon of Holy Prophet (SAW),,, it is all about equality ...