With a playerbase of some 35 million people, Overwatch is a global phenomenon that, for the time being, is more or less the poster child of what a current generation game should look like. For the first time in who knows how long, a multiplayer-only game is not only surviving its first year but is actually gaining new players, releasing new content on a somewhat slow but consistent basis, and branching out into other forms of media that people are consuming. There is no doubt that for the most part, people love the game, even if there have been a few speedbumps here and there. Of course, Activision Blizzard isn't content on merely letting their shiny new toy sit in a glass display case only to be taken out every once in a while, so they're throwing around the idea of creating an Overwatch movie.
This is no new concept to be sure, as there have been a number of games that have had or were in the process of receiving movie adaptations in the past. Anyone who knows their gaming history however would tell you that video game movie adaptations tend to be rather mediocre at best, and outright unwatchable at worst. For example, Warcraft, Hitman, and Assassin's Creed all had movies with multi-million dollar budgets, and in all fairness they did make a fair amount of revenue (whether or not they were profitable is another issue), but they were ultimately considered to be quite sub-par as far as movies go. One can even argue that the only reason that such movies registered on people's radars in the first place was because of the source material, and if they were released with any other title, they would've likely bombed in no time at all.
The point being that at the end of the day, movie adaptations of games are, historically, just not good movies. It doesn't help that there's a myriad of reasons why games translate poorly to the silver screen, and as it turns out, people don't really care about a movie's setting and whatnot when all they really want is a good movie. That is the root of what should be everyone's concerns about an Overwatch movie: whether or not the movie would be worth watching. You can have a perfect, star studded roster of actors and actresses to play every single Hero imaginable, a musical score that could bring everyone to tears of joy when they hear it, and the combined might of every noteworthy CGI and animation studio in the world working on an Overwatch movie with an unlimited budget, but if the movie is just bad, then it's just bad.
Things get even worse when you consider the source material that someone would have to work with. Unlike many other games, there's no singular protagonist in Overwatch. You can argue that the original members of Overwatch should be the main characters of a hypothetical movie, but then what about the other dozen or so Heroes that currently exist in the game? Are they just going to be ignored despite the fact that they have proven to be quite popular? What subject would the main story revolve around? Is the movie going to be on the darker, more serious side of things considering how the Omnic Crisis was a literal world war, or is it going to be a more sanitized version of the conflict? Even if you ignore all the creative hurdles, there are no shortage of practical ones like whether or not a mainstream audience would care about such a movie.
That being said, if such obstacles were to be overcome, then an Overwatch movie could prove to be quite successful. Give fans what is basically an extended version of the existing shorts with the usual roster of voice actors that they know and love from the games, set it during the last days of Overwatch and the birth of Talon, and you have something that might pique the interest of many. The movie could then follow the top members of Overwatch as they slowly drift apart, perhaps concluding with the events that led up to Reaper's attack on Winston in the Recall short. This way, more insight is given into the game's lore without interfering with Blizzard's future plans for the story.
On the other hand, a TV/web series might prove to be even more successful than a traditional movie. After all, why jump straight to a movie adaptation when, from a practical standpoint, shows like Game of Thrones and Stranger Things are just as popular, if not more so, than your average movie? People can watch whenever and wherever they want, Blizzard can still monetize the heck out of each season or episode if they wanted to, and they'd generate near constant discussion about the franchise every week for months if done correctly. There's also the added benefit of such a format being better suited to following a cast of over two dozen Heroes from around the world.
Regardless, the fact that Blizzard feels comfortable throwing out the idea that Overwatch could be turned into a movie and people are taking it seriously is a good sign for everyone, even if this idea could potentially end up being nothing more than an idea. More potential content for fans, more incentives for Blizzard to continue to support Overwatch outside of the game itself, and healthy discussion over the future of the game are things that certain developers and publishers would kill for right now, especially when everyone is under a microscope for microtransactions these days.