Cheap ploy. Most people here expect Moschiach to come from a yeshivish or, ok maybe, a chasiddish community. So, his language will be according to the school he attended.
Of course, one could observe that Jewish leaders were always expected to communicate well with the world – from Moshe’s education in the palace to R Gamliel having 1000 Torah students and 1000 Greek students in his household … So, either Moschiach will have to come from YU or Lakewood needs to improve on Yinglish classes. Maybe, though, Moschiach will come from lepers in Rome as Gemora suggests, so maybe he’ll speak Italian with the Pope.