I’d say it’s a significant part of the games identity, and you need no further proof of that than how divisive the fans are over this.

First person view was only available for the Battle Mode minigame

what exactly would the game gain by being third person? why do you need to see the back of your character’s head to be happy?

If you are doing a sex act with someone of the opposite sex it is a 100% straight sex act. People have orientations, actions do not.