How many times do we hear the phrase "they say"? It is used as a confirmation of facts or to demonstrate a point all the time. However, the "they" in that phrase is no longer a reliable source. When my Grandmother said "they say" to give advice about children she was referring to experienced Mothers or medical professionals. Unfortunately, today the most common source for “they” is social media which is unreliable at best because the root is likely some athlete, celebrity, or politician that are clueless on the subject.
It is important for us to ensure our "they" is a reliable source before repeating it because when we say it we become the "they" for anyone listening.