Think about how Google can algorithmically and manually determine the commercial intent of your website – think about the signals that differentiate a real small business website from a website created JUST to send visitors to another website with affiliate links, on every page, for instance; or adverts on your site, above the fold, etc, can be a clear indicator of a webmaster’s particular commercial intent – hence why Google has a Top Heavy Algorithm.
But Google isn’t the only reason why keywords are important. Actually, it’s less important, because you should always focus on the user: on your visitors and potential clients. With SEO you want people to land on your website when using a certain search term or keyword. You need to get into the heads of your audience and use the words they use when they are searching.
Your SEO keywords are the keywords and phrases in your web content that make it possible for people to find your site via search engines. A website that is well optimized for search engines "speaks the same language" as its potential visitor base with keywords for SEO that help connect searchers to your site. Keywords are one of the main elements of SEO.