The "Intentionally add images to your documentation" heading in the article summarizes my position on this topic well. Screenshots can be a useful learning aid

The "Intentionally add images to your documentation" heading in the article summarizes my position on this topic well. Screenshots can be a useful learning aid. For example, if you are guiding someone through a complex product action which involves several steps, a series of screenshots can be helpful. If you are writing a tutorial, having a screenshot of output (i.e. a web page, an image, a UI) is useful for readers so they can visually match what they have to the result you have. (This is not applicable for text-only outputs).