There's a difference between policing your own content and making some of the most divisive tags optional.
Sure, if the central romance of your game is with a trap character, making that optional would be pointless, or if your game is about a girl falling in love with her horse, but if both are just one possibility out of dozens, it would be pretty foolish to insist on them as unavoidable thereby making the game uninteresting for a large group of players.
After all, as a dev you want as many people to enjoy and play your game as possible, unless you are one of the pseudo-artistic farts (ahem dual family *coughs) who "make their game for themselves" and not for others to play.
So it will always be a case of weighing your options, whether to insist on something to be unavoidable or not.