The invisible, indelible boundary drawn by smell depicts the severe inequality in South Korea through two families in the Oscar-winning film “Parasite.” But the movie dives more into the country’s social problems, running deep and wide.The South Korean film won big Sunday at the 92nd Academy Awards, including becoming the first non-English language film to win best picture. Bong Joon-ho, who won best director and best original screenplay, became the first Korean filmmaker to win those prizes. Fans were jubilant on Twitter and Instagram.“Parasite” stunned the audience with an adrenaline-inducin…