I personally disregard anything that is opinion from anonymous sources. It is literally a worthless opinion, regardless of topic. The worth of an opinion is largely based upon knowledge of the source. Is it someone I trust? Is it someone I respect? Or is it someone who has been consistently incorrect or shown to be a liar? If the opinion held is worth sharing, then it is worth sharing with attribution to a real person. You need to have skin in the game.
Sometimes it is important to share an opinion in order to inform change, be it societal, policy, etc. Silence is the acceptance of the status quo. But again, choose your battles judiciously.
A lot of the replies really zero in on the example topic of incest, rather than abstracting actual subject. Like delving into the backstory of the characters in a word problem. Weird.