Updating past content helps SEO. Improving existing content for keyword rankings within striking distance, or already at the bottom of the 1st page for search results, is often time better spent than creating something new. Google improved their algorithm in the past to display fresher results.
Here is a great way to improve freshness… have a key page pull related category feeds from the site’s blog. This will populate fresh content if you have a regular posting schedule. This also targets year-based phrases, like any keyword followed by 2020, since publish dates can be shown.
This mostly affects events, recent news, hot topics, research, and similar intent behind keywords that imply a need for the latest updates. This applies to many subjects and industries though. The content still must be excellent, since fresh external links to the page matters too.