I vagually remember that but it's been so long since I played the Ezio games it didn't stick in my mind the way it does playing Unity right now. I think I'd honestly have to play them back to back in order to compare but I don't really feel like doing that.They do that with Italian in the Ezio trilogy as well. Supposedly in that game it was explained as being a glitch in the Assassins' Animus, which led to bad Italian accents and words not being translated sometimes. Considering that Unity's story is a hack sent out by the Assassins, that's probably what did it.
I mean, the explanation probably won't make it less annoying, but at least there is one.
But yeah, as usual, any problems can be handwaved by "THE ANIMUS DID IT!". Hell, like half of Odyssey is implied to be this because they were using 2500 year old skin cells or something and apparently filled in the gaps by feeding Herodotus's writings into the animus. This apparently explains why the animus can't tell if the DNA is from a male or female so just lets you pick one.