Gal Shachar is offering the hard sell on headless content management systems:
A truly headless CMS eliminates the head portion altogether, leaving just the back end. In other words, there’s no dedicated system for front-end presentation. And while you might initially wonder if this type of structure might be to your disadvantage, it’s actually the best way to display content to your site visitors on all devices and interfaces, putting your agency in the best possible position to scale.
A good overview of alternative CMS-oriented web strategies. But headless introduces new problems for content wholly decoupled from the web. HTML has a job to do, and it does it well.