SEO isn't dead, but the days of obsessive-gimmick-pseudo-SEO are over.
Today, keywords still matter, but work more in favor of local businesses because Google (the number one search engine) returns local and personalized results first. For years, marketers have been selling SEO strategies and techniques that promise substantial traffic and ranking, but most of these methods have been since proven to be gimmicks.
These SEO ploys came on the heels of the DIY website revolution, where everyone who downloaded a WordPress theme became a website designer. Most people didn't know how to edit the HTML, CSS or PHP files for on-page SEO purposes, and that was fine because plugins took care of all of it. The only thing left to sell the masses was a bundle of off-page SEO tactics that ranged from link building techniques to content distribution strategies.
The biggest downfall for SEO came when content distribution was mistaken for the need to steal content and reproduce it in full. This was done mostly through RSS, and ever since Google slapped down a bunch of link farms, people have been hesitant to use RSS feeds at all. However, RSS is still one of the most powerful resources you can leverage to give your site a boost.
The point isn't to use someone else's original content in full, but to pull just enough headlines through an RSS feed displayed on your website to keep your content fresh, updated, and relevant.
Here's how you should and shouldn't do it:
This article on how millennials are changing the American workplace correctly leverages the power of RSS feeds for SEO for the following reasons:
One of the biggest SEO gimmicks ever sold was the idea of creating exponential backlinks by submitting links to your articles to hundreds of RSS feed directories. Unbeknownst to most people, those RSS feed sites didn't parse the content.
To check if an RSS feed is being parsed, right click on the webpage and choose "view source" to see the source code for the page in question. Use control+F to search for any portion of the text you see displayed in your RSS feed on the webpage. This could be the article title or the first few words of the article. If you cannot find the same words in the source code, your feed is not being parsed.
Any website that scrapes content in any form, including through RSS feeds, is an example of what not to do. Scraping is considered a "black hat" tactic and should never be used. The difference between using RSS feeds to give your website a boost and scraping is that content scraping is literally stealing someone else's original content. Using RSS feeds to boost your SEO efforts requires no more than feeding in article titles, dates, and the first couple sentences as a description.
RSS is designed to syndicate content, not steal it. When used legitimately, there is no need to extract entire pages from someone else's website. Unfortunately, spammers discovered the power of RSS and started using it to steal content, which led to duplicate content problems that punished the original website. Google's Panda algorithm update somewhat fixed those issues, removing most scraper sites from their index.
RSS feeds are legal to use on your website
You may have noticed RSS feed syndicators don't usually allow you to display the entire article or page, and force you to choose a character limit for the description. Displaying anything more than the article title and a few sentences could not only get you in trouble with the original author, but could also create duplicate content problems. Programmers know this and do their best to limit people's ability to display content beyond what's generally considered fair.
RSS feeds should supplement existing content
The bottom line is that using RSS feeds on your website for SEO purposes is not a way to avoid creating your own unique content. RSS feeds are designed to syndicate content, and should only be used as a supplement to your own amazing content.