English is the international lingua franca of academia in a lot of subject areas. But if it's a conference of people studying Israel and/or Hebrew language and literature, you would assume that they know Hebrew. The French would find it inconceivable to host conferences on French literature in English. Everybody who studies French literature is supposed to know enough French to follow a French presentation. The same is true for German. But apparently not for Hebrew, nor is it for Arabic . One other point: In the humanities, language is important for expressing your thoughts. And usually you do it better in your mother tongue. It seems to be hard to comprehend for some, but the overwhelming majority of people on this planet do not have English as their mother tongue. If you write in English, your publications invariably lose some subtlety and precision. In some subject areas, this cannot be avoided if you want to reach a substantial scholarly audience. But in some subject areas, like Hebrew and Israeli studies, you should be able to safely assume that your target group reads Hebrew anyway, so why not write or talk in the language you know best?
UN aid chief says no warring parties observed Yemen truce (Reuters)
from the article: Professors fume over dominance of English language in Israeli academia