It is quite odd for me as a Jewish man to see that this is any type of news to people.
Jews recognize that much of the ritual and even style of our Hebrew worship was shaped by the ancient world we lived in. Our worship style has the earmarks of the ancient Mesopotamian world we were part of, and it extends far back further than the Second Temple era. The religious connections predate our time in Egypt, and festivals like Passover may have connections to the world Abraham came from with alterations to these Mesopotamian feasts made to give them new meaning in our Jewish context as we ourselves were shaped by history.
But prior to the Shoah, antisemitism and anti-Judaism sentiment rose to the point that Gentile people got most of their "firsthand" information about the Jews and our history from Christians. The Church had made the Hebrew Bible it's own document, and in so doing often reshaped its interpretation to fit its needs, often claiming that its views had merely been transferred from Judaism to Christian exegetes.
After the Shoah there has been a greater emphasis on dialogue with the Jewish people by Christianity, and the discovery of the Qumran scrolls did much to lift the "exclusive scoop" Christians claimed of the Bible back to the peoples who were responsible for its foundations.
Add to this that about the same time the Roman Catholic Church gave a nod to critical analysis of Scripture and ever so slowly the rest of the world began to see that the Jews draw a line to their neighbors more than the heavens when it comes to these matters.
The Jewish explanation of these facets is still not fully believed by many, and there is even a pseudo-religious movement that is intent to change the Mesopotamian connection into one that begins with Egyptian religion, even though the critical analysis agrees with Jewish history and it's claim to have adopted things from its more immediate neighbors (not that there is no connection between Egyptian and Mesopotamian religion, as a matter of fact).
In the end, if you have been exposed only to the Jehovah's Witnesses and their literalist approaches, you might still be surprised by information like this. It's very, very old news to Jews. People often think we don't know these things because in the past Christians have drawn their own ideas over these matters and presented them as Jewish history, but you are late to the party if you think it's news. Even as early as the 1950s, the Catholic Church disavowed such previous views and currently its own study Bibles identify the same links regarding Jewish religion to its Mesopotamian neighbors.
The shadows of the Watchtower are very dark and have robbed too many of seeing the world as it truly is.