I think it's what the story wants to convey though, that emotions are a lot stronger than our instinct. Remember when kaoru turned away rin when he remembered the uke calling out to him and them pushing away their fated pair for the one that they truly love
but in the omegaverse universe fated pairs are the people who you'll love from the depth of your heart and will never breakup, no betraying or betrayal i don't think they're happy in my opinion, i think taiga would be alot happier with yuka, it may be just my observation of this story but i do think they're forcing themselves to adapt to the situation.
that was sort of the whole point, going against the usual omegaverse trope of fated pairs, and instead having pairs consent to being together(or at least choose to be together.) Also, every omegaverse story handles it differently. In this one, fated pairs just get a bit hornier around each other tbf. Kaoru proved that he made the right choice when he chose Yuka over his fated pair-its all about emotional connection over instinct.
this story makes me think alot about the butterfly effect and how irrational decisions from teen years can affect humans as adults, it's either a blessing or a curse and makes me wonder about what would've happened if taiga marked yuka and things didn't go the rough path for both of them, also makes me question which one is stronger?is it instincts or emotions.