The author meta tag is a modest thing whose honest value has shifted over time, so what it is, what it does and does not do and whether it is worth your attention:

What it is: meta name author content, a tag in the head naming the author of the page's content, a simple piece of metadata stating who wrote it. It is straightforward and long standing, part of the general set of meta tags describing a document.

What it does and does not do for SEO, the honest part: the author meta tag is not a significant ranking factor, search engines do not meaningfully rank pages higher for having it, so anyone adding it expecting an SEO boost is misinformed. Its value is documentary rather than ranking, recording authorship for readers, tools and content management rather than moving you up results. Being clear about this saves effort spent on it as an SEO tactic it is not.

Where authorship genuinely matters now, the important redirect: while the simple meta author tag is minor, authorship as a concept matters increasingly through structured data, since Google's emphasis on expertise and trust, the E-E-A-T ideas, is expressed through proper author markup in schema.org structured data, an author with a real profile, credentials and an established presence, rather than a bare meta tag. So if authorship matters for your content, a news site, expert articles, health or finance content, the effort belongs in author schema markup and genuine author authority, not the meta author tag, which is where people conflate a minor tag with a real signal.

The practical answer: include the meta author tag if you like for documentary completeness, it does no harm and records authorship, but expect nothing from it for ranking and if authorship genuinely matters for your content's credibility, invest in structured data author markup and real author expertise, the actual mechanism by which authorship influences how content is trusted and surfaced now. The bare meta tag is harmless housekeeping, the schema and the expertise behind it are where authorship does real work.