‘Bas mitzvah’ would generally identify one as from a more traditional Ashkenaz background where Yiddish was likely spoken at least at one time in the past.
‘Bat’ would indicate being more comfortable with modern Hebrew, or perhaps from a Sefardi background.
The same breakout is sometimes evident in pronouncing something as common as Yis-rah-AYL vs. Yis-ROH-ul for Israel.
Where I am is San Francisco, so the local Jews seem to be mainly Ashkenazi US types here for many generations, with a fair sprinkling of new immigrant Israelis.