Yesterday, I was chatting with one of the players in my House of Worms campaign. He mentioned that, growing up in Europe in the 1980s, he learned to play Dungeons & Dragons from the German translation of the Basic Set supplemented by a photocopy of a handwritten French translation of the AD&D Player
Having read OD&D and AD&D 1st edition in the original English, I don't think bad translations would have increased the amount of misinterpretations to a meaningful degree.
Though with the level of quality of the 5th edition DMG, I would say that D&D is still a game that is taught primarily by oral tradition, if you include text conversations in that category. Public assumptions of how to play the game are much more impactful than what is written in the books.
