Comments on blog posts can help improve the search engine optimization (SEO) of a website. Comments are indexed by search engines and can help to improve the visibility of a blog post.
However, Google does not consider comments to be a ranking factor.
Comments can also be used to build relationships with readers. If a blog post is well written and interesting, readers may leave comments that offer feedback and support.
This feedback can help the author improve future posts, which can lead to higher rankings in search engines.