Why do heimish and Torah True people all but refuse to use English for the following words:
God (Hashem, Ribono Shel Olam)
Israel (Eretz Yisroel)
Black person (shvartze)
Many more in the comments.
It's weird. You'll see people who can't talk their way out of an Israeli paper bag, self consciously switch to Hebrew for these few words.
NB: I understand some Hebrew words offer a different connotation; other words (like shul (yes, it's Yiddish, I KNOW!) are just warmer than the English. But I don't think these explanations apply to the examples above.