Not anti-Semitic at all, says this Jewish chick. He’s calling the tradition stupid, he’s not saying Jews are stupid. Well, he may be calling the Jews who follow this particular tradition stupid (but not necessarily all traditions–although there is at least one poster who’s saying that, but it isn’t the OP, and that person’s not confining it to Jewish religious traditions anyway).
And yeah, Jews have been arguing among ourselves for millennia, and I am pretty sure many have found and called their opponents’ views moronic. Heck, debating and shouting down your opponents are integral parts of Yeshiva scholarly life. Name-calling is probably not, uh, kosher, but outside the rarified atmosphere of school or temple, even among friends/family and other mishpocha like at Passover or some other gathering, the arguments can get pretty heated. If we were all too dainty to call each other names, Yiddish wouldn’t contain so many colorful, vulgar and not-necessarily-anatomically-possible insults.
So FWIW, it gets a pass from me.
Cripes, things around the SDMB have become vastly improved over recent months, knock wood, and that includes more interesting, lively Pit threads. People with delicate sensibilities are well advised to keep clear.