From the Daf Review-
"5)
The Beraisa tells the story of Savta ben Elles - a plain Yisrael, who rented his donkey to a Nochris."
Question, not a correction- What is meant by a "plain" Yisrael? That he was not a Kohain or Laivi?
No, it is not referring to a Kohen or Levi. Rather, the intention is that he was not a great Rabbi, or a very rich person, or some other kind of eminent figure. (Possibly in Yiddish usage one would say he was "a Poshiter Yid.")
Kol Tuv,
Dovid Bloom