What's even the purpose of marketing "gurus"?

I mean, those lunatics that spend 12h/day making cringe posts on LinkedIn everyday, like boasting about going to "work" 5am to 9pm, raving about the fact that work-life balance shouldn't exist as a term, and that sort of stuff. Who even pays them? what's the incentive in humiliating yourself like that in the digital public square?

Are businesses/corporations dumb enough to "hire" these people with the credibility of the guy on the beach trying to sell you a totally non counterfeit Gucci for €10 (negotiable to €2)? Worse, do random people/consumers/job-seekers fall for them?

I want to believe they're just bots, but sadly I know of a few who also happen to exist irl