The post doesn't read like the user thought the tips constituted any type of security issue. They might have thought it was expected, but not well known, behavior.
The macOS vulnerability was apparently a known thing, POSTED VISIBLY on Apple's own forums, and it reads as if the user got this "helpful tip" from somewhere else.
This is pretty nuts.
High Sierra went gold on September 25. Beta 1 came out in June, I think.