All of my coworkers are women, and without exception, they are observably addicted to Facebook, Twitter, and other social media. They post and like and Tweet and share and upvote and forward until they lose track of who they are, where they are, and of what they’re taking notice. Just watching them makes my arthritic thumbs ache. And yet. Out of the entire gossipy solipsistic backstabbing shallow juvenile selfie-taking gaggle of them, not one — not ONE, mind you — knew what “Let’s Go, Brandon!” means, nor anything about the phrase’s origin, nor why it’s considered funny. Not one. I have a firm grasp of the concept of duty, and…