For a non-YMYL page, an author byline has limited direct ranking effect. Its real value is trust and transparency, telling readers who stands behind the content, plus a minor contribution to how credible the page feels, which is far less critical than it is on YMYL topics like health, finance, or legal advice. So the calibrated answer is to add bylines for genuine transparency, not to treat them as a ranking lever, and to resist the EEAT theater that bolts author boxes onto everything on the assumption they move rankings.
The reason the effect is limited here is that author credentials carry the most weight where the stakes are highest. On YMYL subjects, who wrote something genuinely matters to whether the advice can be trusted, and the quality systems are more attentive to expertise and authority on those pages. For a recipe, a product roundup, or a hobby guide, the same scrutiny does not apply with the same force, so a byline is not what determines whether the page ranks. The content’s relevance, coverage, and usefulness do the ranking work; the byline mostly does reassurance work.
That distinction is what the cargo-cult misses. Adding author bios sitewide “for EEAT” treats a byline as a switch that lifts rankings, when on non-YMYL content it is closer to a courtesy than a factor. A thin page does not become rankable because it now names an author, and a strong page was not being held back for lack of one. Worse, manufactured author boxes with invented credentials add fake trappings without adding trust, which is the opposite of the transparency a byline is supposed to provide.
So on non-YMYL pages, add a byline when it genuinely tells the reader who is responsible and builds real transparency, and skip it as a ranking play. Put your effort into the content’s relevance and usefulness, which is what actually ranks here, and reserve the heavier author-credential investment for the YMYL pages where it carries weight. Right-size the factor instead of performing it.