Updating old posts wins almost every time, especially if those posts already have some backlinks and authority built up.
I run several travel and hospitality websites, and here is what I have seen from direct experience: refreshing an existing article that ranks on page 2-3 can push it to page 1 within weeks. Publishing a brand new article on the same topic would take months to achieve the same result because it starts from zero authority.
My content refresh process:
1. Identify pages that have declined in traffic using Google Search Console. Sort by pages that lost the most clicks over the past 6 months.
2. Update outdated statistics, prices, and references. For my travel niche, things like pricing, regulations, and seasonal info change constantly.
3. Add new sections that cover questions people are actually searching for. Use Google's People Also Ask and related searches to find gaps in your existing content.
4. Improve internal linking. When you update an old post, link it to your newer relevant content and vice versa. This distributes authority across your site.
5. Update the published date only if you have made substantial changes. A minor edit does not justify a date change and Google can detect that.
That said, you still need new content to cover topics you have not written about yet. The ideal strategy is a mix: spend 60-70 percent of your content effort on updating existing posts and 30-40 percent on new topics that expand your topical authority.
The biggest mistake I see is people who keep publishing new thin articles while ignoring their existing content that is slowly losing rankings. Fix what you have first, then expand.