Tom Stoppard’s wrenching drama “Leopoldstadt,” which I recently saw on Broadway, begins in 1899 at a Christmas party in the Vienna apartment of Hermann Merz, a prosperous and assimilated Jewish businessman, who is married to a Catholic and nominally converted. Merz is convinced that the antisemitism that plagued his forefathers is fading into the past. There’s still plenty of anti-Jewish prejudice around, he acknowledges, but nothing comparable to what prior generations endured. The rest of the play, which ends in 1955, chronicles how misplaced this confidence was. Seen in 2022 in New York, it felt like both an elegy and...