In the post you mention extending the first class, author-bio, to the article class. When you introduced the idea of the media-card wouldn't it make sense to have both the author-bio and article classes extend from it, maintaining the semantic naming but also making it easy to override or change some style for one in particular?
Overrides are special cases. Usually you start with one, but before you know the CSS file has bloated to thousands of lines with hundreds of overrides depending on context. With enough of them you can't comprehend the CSS anymore, which means you can't change any existing classes, and so the CSS becomes write-only.
