Most of the people preaching "authenticity" in marketing are not being authentic in their marketing.
They're in it for the applause. And you can tell in a heartbeat.
Authentic marketing means you're not in it for the applause.
Being an authentic marketer means you have a monster living in your chest cavity, and if it doesn't get out it will rip you apart from the inside.
You do your work because you have to. Because not doing your work horrifies to the point of physically shaking.