Hasn't this strawman been knocked down already?
No. Christianity is definitely a separate religion from Judaism. Christianity is open to non-Jews, does not ask anyone to convert to Judaism, does not require people to adhere to the abominations of Leviticus, does not require adherence to any Jewish holidays or customs... it is a new and separate religion. There is no indication in the OT that the prophets who spoke of a Messiah meant someone who would establish churches of a competing religion in the heart of Jewish territory.