The website already serves a 496 byte CSS file (359 minified, even less gzipped), addition of a max-width to make it readable on large screens wouldn't make a difference.

It's not optimized to that level. There's 1.1k of inline tracking javascript. And a reference to an external stylesheet for the styling, along with a bunch of wastefully long hex identifiers.

Took a look at the dev console, there are 2 tracking scripts, segment and CNN specific one. Those take up the majority of bandwidth. There's also a separate CSS style sheet. The main DOM and the stylesheet are <10% of the total bytes transferred. The favicon is the same byte size as the entire DOM.

Don't think there is necessarily a consideration of byte cost, given the size of the tracking scripts. A few lines to make this manageable on wide monitors aren't prohibitive for those users.