It's less that games shouldn't be political, but that they are always lopsidedly political on one end without alternatives in the "free market" because the games media, publishers, and corporate executives more or less strangle any nascent gaming company that deviates from the political orthodoxy in the cradle. If there was a true free market where everyone is free to find games that reflect their values and preferences, people wouldn't care. But active marginalization of a large section of the population via top down corporate advertising censorship campaigns and smear by guilt through association has completely distorted the landscape of commercial art, of which gaming is a part of.
The threat "it would be a shame if your game with the wrong values and politics were subjected to a smear campaign by gaming journalists who moonlight as political activists, making your game unpublishable as no advertisers or capital would want to touch it, and we'll namecall those workers who decide to work for you to make sure they are blacklisted in the industry" has smothered any viewpoint and narrative diversity in the industry.
