Is it?
In terms of programming/graphics, the former requires much more ressources. The latter requires ... good writing. Yeah, that's a problem, ofc, when it comes to video games. ;i
No, it really is unfortunately. I feel exactly the same way as the OP, made a similar point years ago at the old place, and wondered why only games have this problem. Yes, movies also have lots of violence and action. But while games mostly revolve around shooting/stabbing/punching various humans/monsters/aliens for 80%+ of game time, even the majority of violent movies aren't that weighted towards violent screen-time. And more importantly, movies have plenty of films without that kind of overt violence, like drama, romance, comedy, thrillers, documentaries, still within the "AAA" space. You either have to look for Indie games if you want that in video games, or look at the sports genre (the only other big type of game genre besides violent action).
Video games don't have a King's Speech, Breakfast Club, Lion King, Life of Brian, Interstellar etc. We pretty much just have violent action and sports in the AAA space.
As for programming of dialogue for engaging and varied gameplay, Deus Ex Human Revolution did this INSANELY well. I called them dialogue boss battles. But they were few and far between. The voice acting requirements, animation requirements, and none of it can easily be applied to repeatable sandbox gameplay like guns can =(
And when AAA games HAVE to sell big or risk destroying the company these days, it's not surprising that the vast majority of devs decide to base their games around violence and reveal them with comments like "Check out our awesome combat system!" - Simply because violence as a gameplay mechanics has been polished to a fine sheen and reliably sells. We need to hope the smaller devs who can afford to take the risks are able to find systems as deep and sanboxy as violence has been perfected towards in games, that AAA games can then adopt.
Sometimes I think there's hope -
No Man's Sky is amazing for constantly prioritising improvements to exploration and non-violent gameplay, with combat always being a minor back-seat part of the game. It's sold millions and is (today at least =P) almost unanimously loved by those who play it.
Fallout 4's settlement system allows you to play this game with combat taking a back-seat too. You can literally build your character around construction, science, engineering, and only occassionally have to engage in violent conflict in the times you run out of materials and need to venture into the wasteland to scavenge for more. The game is flipped from being a violent conquest of the game world, to a community-driven resettling of the game world. That's amazing.
We're finally also seeing a AAA game going out of its way to avoid combat almost entirely in Death Stranding. Another huge plus for the maturity of the industry and how it will look to non-gamers. Not without its speed bumps though, because like haters of No Man's Sky and Fallout 4's Settlement system, there are plenty of people hating on it simply because it doesn't instantly convey the same usual violent gameplay loops they're used to in games. "Walking simulator" and "But what do you actually do?" are getting time in the spotlight again...
