I guess I'm a little confused. With this being a different time line, why do some people think that certain things will happen? The destruction of Praxis may not happen. Q may be kept in check by his superiors and never introduce TNG crew to the borg. There may not be a Q. We already know that things look different and happen differently from the movie.
If there are different time lines but every one plays out the same then what is the purpose of different time lines? Spock Prime's presence has already altered the timeline here and he could do further damage by baring his soul. What if some over heard him telling someone about something and used that in a negative way?