The evidence that this was a business move was the fact that they hyped it. I forgot they actually made overwatch comics, and it was only when every social media circle I belong to exploded into "OMG A CHARACTER IN OVERWATCH IS GBLT" that I remembered. Who they chose for this stunt didn't really matter. However, there were a lot of people "shipping" Tracer with other female characters from the game, so I think they decided to cater to those fans and just make Tracer officially gay. I think the idea is that the comic will eventually turn readers into players.

But honestly, I've seen very few examples of characters that are gay for plot reasons or are gay "just because." It's almost always treated as a big surprise to get people talking about the "thing" again. I honestly don't think a lot of people read the comics, and this was done to increase readership and get the comic views up before the end of the year. But who really knows?

Sadly, business politics can be quite parasitic when they creep into our entertainment. Maybe when people stop getting exited/offended over a character's sexual preference we'll stop seeing this kind of abuse.