I didn't, but it doesn't really change my point. It makes no sense to ding the mormons for using the term "Old Testament" unless one also dings the Christians for using it. There are plenty of legitimate objections to mormonism. This one is silly.
In fact, if indeed the author is Jewish the rest of that paragraph is as much a condemnation of Christianity as it is of mormonism.
In the article the author claims to be Catholic. If you can legitimately make “Jewish” out of that then words truly have no meaning unless you posit that the author lied.