Contrary to what you might have heard, Chris Pine is not trading in his leading man credentials to play the love interest in Wonder Woman. His character might take on the classic damsel in distress role, but Steve Trevor in Wonder Woman is not your average superhero love interest, relegated to the background. Pine's role in Wonder Woman is arguably the biggest love interest role in a superhero movie to date, and to me, it seems clear that because unlike nearly all other superhero movie love interests, Steve is a man.
When we first meet Steve, he's crashing into the ocean off the island of Themyscira after heroically stealing covert documents from the Germans. His first interaction with Wonder Woman is when she saves him from drowning, but throughout the course of the film, Steve proves himself not only to be competent in battle but instrumental in Wonder Woman's success. He helps her get to the WWI battlefield, follows her into the "no man's land" to storm the German trenches, and fights right alongside her to help save innocents. Not only that, but Steve also helps teach Diana about the world outside of Themyscira. He is, in many ways, invaluable to her journey in the film.
This would be totally fine, except that Steve is one of the only romantic interests in superhero movie history to get this kind of screentime and narrative impact. In the DCEU (DC Extended Universe), Lois Lane (played by Amy Adams) is relegated to the sidelines; in Batman v. Superman: Dawn of Justice, for instance, she had almost nothing to do except be naked in a bathtub and be sad over Superman's persecution. In the MCU (Marvel Cinematic Universe), meanwhile, love interests like Pepper Potts (Iron Man) and Hope van Dyne (Ant-Man) are continuously kept on the fringes of the action, far form the meat of the film.
In comparison, after Diana and Steve head to London, there are only two scenes in which Wonder Woman appears without him. It's hard to look at Steve's role in Wonder Woman and not think that his version of a love interest was upgraded because he's a man, and men, even in supporting parts, are not cast aside easily in Hollywood like women so often are.
When asked about playing a damsel in distress character at CinemaCon, Pine himself rejected the classification. "The question doesn't service anything but this narrative of hierarchy," he said, via Yahoo. The actor went on to say that he sees Steve as equal to Wonder Woman, despite his not being as superhero. "I think this is a movie about parity," he explained. In a separate interview with ET, Pine laughed about being called a damsel in distress, making the point that women are never asked how they feel about being the damsel, when he gets asked all the time. "But you'd never ask Amy Adams that because it's demeaning," Pine said.
And he's right, it is demeaning to be stuck in a damsel in distress/love interest role. The role of Steve Trevor, however, is not demeaning — not one bit. Pine's role in Wonder Woman is far bigger than the typical damsel in distress. He even, without spoiling the movie, gets a superhero-worthy conclusion to his plotline in this movie, reminiscent of Captain America in Captain America: The First Avenger.
At CinemaCon, director Patty Jenkins said, "I don't think anybody wants that [the damsel in distress] out of any love interest. Not either gender." And her film reflects her desire to avoid the damsel stereotype. Wonder Woman does its best to break the superhero mold and remake the love interest role into more than a two-dimensional plot device. It's refreshing to see a love interest be able to be as valuable on the battlefield as he or she is off of it. It's refreshing to see a damsel in distress fight alongside a superhero. But you know what would be even more refreshing? Seeing a female love interest get to do all of that, too.