My brother, you have asked the right person. I am an American who had never heard of Hindus until after I got involved in Sikh Dharma. It would be foolish to think I and my other western brothers and sisters are blindly following caste or other parts of Indian culture. We are not following anything actually. We are creating our lives moment by moment, day by day, and in that we are leading.
The dharma itself may not evolve, but the support systems and environment does. So in current times we have tape players. We can have Gurbani Kirtan playing 24 hours. We have modern weapons to use. We have airplanes so people from all over the world can visit Harimandir Sahib. The way we interact and teach the public is evolving, but don't get that mixed up with the internal life.
Everything in our Dharma is designed for evolution of the *Soul*, not the body. The body is made as it is for a very specific reason. Every hair on the body plays a part in your consciousness and how you perceive the world. Though the outer world may change, people still need one thing - to realize they are part of the infinite One, and this world is temporary. We come here as beings of spirit to experience the human form, not the other way around. Yes there are hassles involved with being a person of character and consciousness. animals don't have restrictions on their behaviour, humans do.
Please check out this web site for more in depth discussion. http://www.sikhnet.com/Articles