I mean, considering that a main plotline exists, anything outside of it is always optional to begin with. By that I mean experiencing every single route is a personal choice. Nsfw scenes are also optional. Its purposefully made. Do you fr think that making only few (Nauxus and Thane in this example up until now) characters romancable as an option to be a chore? If it wasnt forced into a main storyline and the option exists outside of it, just like with every nsfw scene, why not add it? It could also be made in a way that combat doesnt impact the relationship. A chore also already exists, to either unlock nsfw scene with Naux or Axel if starting a new run.
I honestly wish he makes romance possible, even if I know he might not.