yekke2 -“Why is it Jewish?”
Even though the origins are many languages -it is only spoken by Jews.
Ivrit is Not Loshon Hakodesh. They don’t even pronounce the words the same. Many Non-Jews speak Ivrit. Being similar to Loshon Hakodesh doesn’t make it a Jewish language.
So some people feel they have to apologize when they aren’t speaking the Jewish language to Jews.
The reason some speakers spoke English by the Asifa is that they realize not e/o understands Yiddish -so they didn’t want those participants to feel left out.