Same as internal linking, displaying related posts at the end of your article keep your readers engaged. If you want to increase user engagement on your blog, try to understand the psychology of your reader.
When your reader ends up reading your content, he/she will either leave your blog or search for the related information in the search engine.
So to make them engage with your blog, display the list of articles that relates to your post so that they will stay on your blog and will continue reading your other articles.
The benefit of showing related posts makes your readers stay longer on your blog but make sure that you display relevant and related articles, otherwise, your readers might get distracted and there are chances that they will never visit back to your blog.