SEO answer is because the old page has accumulated trust and that age plays role. The developer shared his ideas about why he thinks the site still ranks with outdated content, content that in his opinion is thin, all on HTTP... I also think that age might be part of the problem of trying to provide that newer content. in most cases what we have done over the year is lot more thorough that what was written say ten or twelve years ago... The developer observes that in his opinion, sites that use HTTP tend to have not been updated in two to three years. Google's John Mueller explains the various reasons why web page may continue to rank, even one that uses HTTP and appears to have not been updated in many years.. For example, the process for boiling egg has very remained the same for thousands of years. While new techniques or tools may evolve, the basic content continues to remain relevant.. I think it's tricky and these pages just have built up so much kind of trust and links and all of the kind of other signals over the years where like well it seems like reference page.. Googlers, including John Mueller, have pushed against the idea that Google uses any kind of metric called trust.. That older site does not appear to be adding external links to old pages can be signal that the site continues to be on the level.. The developer picked up on John Mueller's use of the word trust and responded that he had the feeling that the site's ranking success had something to do with long term trust that the page had acquired..
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