If you see a comment and you feel like the person has not read the document, do not tell them that they have not read it. This will probably be interpreted as an insult to somebody's intelligence or reading abilities.

Maybe they have read it, but there is a misunderstanding about the content. Maybe the document is confusing, but most likely this is a result of poor definitions.

Instead of saying that they have not read, use embeds and links to emphasize the content that you think they haven't read. This will highlight the underlying communication issue.