Greetings,
For some oldies, "New Age" began in the 1960's when researcher Marilyn Ferguson started a newsletter publishing summaries of scientific experiments that reported a 'new' physics of sub-atomic matter finds truths that sages of ancient spiritual traditions espoused for centuries: time is not linear, consciousness is shared by all humans and even all life, etc.  A 'New Age' was necessary because old scientific theories no longer applied; since the 3-d'l world of the past was being disproven, a new paradigm was needed.
In the enthusiasm of finding these new truths, some claims were not replicable, and some hangers-on became associated with the term that had no idea what it meant (sorta like in Christianity.) The term 'New Age' sunk to its lowest common denominator, and the physicists who are so buoyed by their new discoveries have quieted due to their now deeper take on spirituality learned from their science.
Many new fields of knowledge have been developed based upon new age findings and are being used in business and technology--unified field theory, psycho-neurolinguistics, transpersonal psychology, and on and on.
It's all one.