You need a sarcasm smiley on that last comment. It's more accurate to say that a love interest has never been so in our faces in any of the TOS movies but even that isn't quite true - we had Decker and Ilia - but in most of the movies the 'romance' element was very understated - we had implied sexual tension between Spock and Saavik, flirtation between Kirk and Gillian, and Spock's permanent boner whenever Valeris was in the room.
Spock and Saavik - no way
Gillian was just humouring Kirk
Maybe there was something between Spock and Valeris