if the person is incapable of, or unwilling to, read documentation which you think they should, you can ask them honestly about it, or ask your manager about it

if management feels this person is unqualified to be in their job, they can take care of the issue

"rtfm" or the AI equivalent is being snarky while dodging the issue that you should just talk about, which is that you think this person is asking you too many questions