Re: The Borg and JJ's universe
The ENT-E crew went back to CORRECT what had been corrupted, and they succeeded. However they failed to prevent several people from dying and had to contaminate the time stream and give assistance and future knowledge to Zefram Cochrane and Lily Sloane.
You are assuming that there was an original timeline that didn't contain any of this. You cannot prove that. For all we know, it's as I suggested - the actions of the Ent-E and crew were always supposed to happen.
"If the world was perfect, it wouldn't be." - Yogi Berra