I didn't say 7 should stay the same. I think it's jarring to just thrust her back in the story changed and not address it somehow. You can't just hand-wave that much character arc away. It has to be addressed in some integral way.
Not only that, but one can make an argument that 7 should never fully transition to being completely human in her personality, similar to how Data lost his uniqueness when he got his emotion chip. I think 7 is more compelling as a character by integrating her Borgness rather than abandoning it completely, similar to the integration of logic/emotion that took place in Spock across the movies.
The concept of 7 as completely human is just rather dull. Just a regular person with a piece of plastic stuck to her eyebrow.
I think I see the source of the trouble here: "Star Trek: Picard" hasn't aired yet. What you saw was just the trailer, not the actual show.
