It is actually very simple: good SEO, Google likes your content; bad SEO, Google won't like your content.

If you're writing a story that goes on Google, ie every single story written for an online publication, you're working for your boss, but both you and your boss are working for Google's algorithm.

The SEO helps Google decide whether people who might be into the type of content your competitors provide can also appreciate your content.

Ignoring the SEO part in your writing is the same as making a great cocktail and then serving it in a plastic cup.