Laskern, that is utter nonsense. Only a small minority even understand more than a few words of Yiddish.
Git, actually a large number of the founders of Aguda were German-speaking followers of Rav S.R. Hirsch. In any case, the founders of the Talmud were Hebrew and Aramaic speakers. Those is EY also spoke Koine Greek. Should speeches have been made in all of those languages?