The B-plot is also a great illustration of the fact that the writers have no idea what to do with Troi. The character was included on the show literally just for sex appeal, and by season 7 the writers were scrambling to justify her existence in a way that didn't openly acknowledge the fact that she was only included because Roddenberry was a womanizing horndog.
Meanwhile if the show had written her as an actual person from the start, she'd have already proved herself a thousand times over. An empath on a ship whose primary missions are diplomatic and exploratory is INSANELY useful:
(a rock monster appears on the view-screen)
"Lower your shields for cultural exchange."
"Counselor, opinion?"
"Despite the strangeness of this species and their lack of outward emotional cues, I sense only curiosity and openness coming from them. We should comply"
Same with Spock, he presents "logical" conclusions where the priors are not knowable from where he stands.
Maybe it is just a popular caricature of logic, that if you are just not purely "emotional", then you are the opposite: logical.
Don't tell people that Spock is not logical though. You'll get an emotional response.