Spock is one of Star Treks if not Star Trek's most popular characters.
I think JJ would be crazy to think he would need to normalise Spock's character to make him more acceptable to modern audiences.
However there might be a bit of truth that in giving Spock a girlfriend then he and Kirk (and McCoy) can have a bromance without being considered gay.
The term bromance has never been used to define gay relationships. Bromance has always been about guys who are best friends, share a great platonic love and affection, and who go through live together. One of the most distinctive things about Bromace is the guys talking about girls or their sexual encounters with women.
A perfect example of bromance are the guys from The Hangover or Joey/Ross/Chandler from FRIENDS.