I don't know why every RPG has to have a companion dating sim component.
Because it became a standard many years ago, that some npcs in rpgs are romanceable and the overall majority of players enjoy and appreciate this.
Its fine when it is done well. However, when it is a required part of every RPG then it becomes something that is often NOT done well. For that reason I would rather it just be left out most of the time. The scene at the party where you finally get with a companion is utter cringe and the game would definitely be better without it.
Put in the time to do it right or don't do it at all. Don't just put in a bad scene so that you can advertise romanceable companions.