Serious answer to a rhetorical question: because he's a useful tool to broadcast the zeitgeist. There was much money to be made by Theranos being viable and those interests who stood to make the most money were most directly connected to CNBC.
Once upon a time the moon howlers were brokers. They have since retreated into Howard Beale impressions because the perversions of the market have become the market and they can't make money anymore. It's now a bunch of bots chattering at each other and the humans can't keep up... and they have this nasty habit of needing to believe that any of it matters. The bots don't care. When this number goes up, do that. When that number goes down, do this.
I can't recommend Carreyrou's book, Bad Blood, enough. It outlines the preposterously simple scam at the heart of Theranos - her next door neighbor was a venture capitalist, he vouched for her, and for the next three years everyone piled money on top of her because she wore a black turtleneck. This is a 1st-semester college dropout who patented something demonstrably impossible, rallied hundreds of millions around her and took a Siemens blood analyzer, broke it, and got Wallgreen's to pay her millions to set up shop in their drugstores.
My wife had me watch the Theranos story closely because she deals with Quest and Lab Corps on the daily and they're awful. Their science is great - we'd be utterly fucked without their chemistry - but their customer support is abysmal. The fact that Theranos proposed a consumer-facing blood-testing organization was exciting to her and, frankly, was the force driving investment. Yeah the magic box would be cool but the idea that you could go buy a cholesterol test with about the same efficacy as buying a pregnancy test was the kind of thing that made investors swoon.
That market is still available. Nobody will touch it, though, because Quest and Lab Corps have a duopoly that nobody wants to attack 'cuz they'll just suck the profit out of it. No, no. We need a magic fuckin' box or else we can't innovate.