I too am bothered by the change, I have asked many people about it and yet I have not been given a good answer. At the end of the day, in terms of authenticity, I find it hard to believe that one is more correct than the other. I think if any of us heard Moshe Rabeinu speak Hebrew it would sound very different. But on the other hand, I think it is important to preserve our mesorah, Ashkenazis for Ashkenazim and Sepharadit for Sepharadim. However, one benefit that havara Sepharadit has is that it doesn’t sound weird to speak with proper havarah (meaning, for most words, emphasis on the final syllable). For all those in here who are devoted to proper pronunciation (at least for Ashkenazim), I say we throw away haVArah AshkeNAzis and start speaking havaRAH AshkenaZIS. Who wants to join the club of speaking AshkenaZIS properly?
