Yup. If you target grown-up geeks, sure, an english only version of D&D may be enough. May be : in my gaming groups, even if all of us read english, we play pathfinder or Ars Magica because the majority is more cumfortable with a french ruleset than with english ones.
But what about kids ? The 12-18 years old are NOT fluent in english. It's better now than in the past, thanks to Game of Throne and Dexter (among others...), but that apply only to oral understanding. The young generation does not like to read anyway. So, asking them to read in a foreign language to learn a complex game is a hard prospect. I'm talking about those guys (well, not those who made the petition or signed it...).
Well, it means that Pathfinder will be the dominant game for a few more years here. It's sad, however, because 5e is easiest for a beginner, and could probably attract more new gamers than Pathfinder.
