It doesn't look like it's changed to me at all. Maybe people are noticing it in game because someone mentioned it (made a big deal of a few phrases). Different packs have things worded differently and how it's worded depends on the one(s) that gets the job of doing it. Most of the latest packs still have a lot of she and he types of phrases including the latest kit. Heck, in the knitting pack we had added in Lord or Lady of the Knits Aspirations and the one you see for your sim depends on the gender you chose for your sim starting out.
Again, I really wouldn't mind a sweeping change to make things consistent (although not sure I'd like for developers to be putting time into doing that). Many of the drop downs, moodlets ect.. I see just refer to your sim as a sim.. but if they did that I'm really sure they would take credit for it.
