Some say the Hexaplex \ murex cannot be right, since Chazal say it was “Nignaz” (hidden). Of all the dishonest arguments against wearing Techeiles, this one wins the prize.
Well then, one cannot live in Eretz Yisrael, either, let alone try to kick out the Erev Rav since Chazal speak of “Galus”. (Even the Satmar Rebbe doesn’t say that, but tries to bring a gemara.)
Do we forbid anesthesia to women in labor since “בעצב תלדי בנים”?
Must we sweat in a copper mine, since “בזעת אפך תאכל לחם”?
You get the idea…
In fact, we know Techeiles was around well after it was officially “Nignaz”.
A related version says the Techeiles remains “Nignaz” no matter what, since the Biur Hagra on Orach Chaim quotes the medrash of “Nignaz”. So, it’s therefore “halacha”. Sorry, way too “deep” for me to understand this one.
(And anyway, why is this claim attributed to Brisk \ Beis Halevi?)