Originally Posted by Jdoughs

The whole benefit to using a blog is the text value it brings to the domain, and the simplicity in adding textual and media rich content. You want to use text just because that's what the site type (blog) itself is based on.

People use the blog as a tool to generate targeted traffic from social media sites and search engines, the use of text is instrumental in that.

There is many other site types or scripts that will create an all photo site, or all video site and deliver the content better. And also many hybrids that are decent at doing both or all, but again, might as well use the medium to its most potential, and in that case its adding text to blog posts.