How Can Hinduism Be Considered Monotheistic When There Are More Than 33000 Gods Goddesses?

How Can Hinduism Be Considered Monotheistic When There Are More Than 33000 Gods Goddesses? How can Hinduism be considered monotheistic when there are more than 33,000 gods/goddesses? All of the other gods/goddesses are aspects Brahman. Why is the cow a sacred animal for Hindus? It produces milk and dung, and Lord Krishna took its form