As I recently said in another thread, pretending Enterprise
an alternate timeline makes it entirely pointless as a prequel. Why show the first Human/Vulcan hybrid if not to forshadow Spock? Why show the beginnings of the Federation if it's not meant to be the Federation we all know and love but some weird alternate version? Why have Brent Spiner playing Arik Soong if not to foreshadow his various TNG characters? Why explain the Klingon forehead thing if not to set up the Klingons as seen in The Original Series?