Hinduism is monotheistic for some, henotheistic for others, polytheistic for others, atheistic for still others. Its vastness can never be underestimated. Hindus, having practiced their entire lives, generally just know one sect's practices in any detail, and have poor knowledge about other sects. A Tamilian living in a village in TN wouldn't know much about a Bengali Vaisnavite.
So for an outsider to come by, read a couple of paragraphs in some introductory book, which also will have a bias, well ... what can we say?
As for intolerance, I think many need to take a better look at what that means. Historically, India has been a safe haven for many groups. Early Christian and Jews, Buddhists, the Baha'i', etc. have all found safe ground in Mother India. Why? the overriding belief system, Hinduism, is so tolerant. But that doesn't mean we need to accept all these diverse and foreign concepts as our own. It just means we can allow them to exist, without interference from us, which, by the way, is the definition of tolerance. It means a unity in diversity. Again, the overriding concept for that POV is ahimsa.