Here, Tasha explains to Wesley the drug addiction she witnessed on the failed colony she hails from (seen in the fourth season story “Legacy.”) Tasha lectures Wesley about drugs from that perspective, but importantly, it is still from a superior, and abstract point of view. By contrast, this scene would have possessed real power -- and value -- had Tasha explained to Wesley that she lived with drug addiction before being rescued. That the adults she lived with, the parents who abandoned her, what-have-you, were drug addicts, whose behavior had deleterious impact on not only their lives, but hers. Better yet, she could have acknowledged that, on the colony, she was a drug user, before her life changed.
So “Symbiosis” is that rare stand out: a story in which the wisdom of the Prime Directive is debated and, ultimately, upheld. Crusher doesn’t like it being upheld, because she is coming from a humanitarian point of view. She wants to stop the suffering and exploitation of the Ornarans. Picard takes a broader view and realizes it is not her place, or Starfleet’s, to decide what should or should not happen in another culture. He is still able to help the Ornarans, in the grand scheme of things, by denying them the coils that will repair their ships. This means that there will be no further shipments of Felicium, and, after withdrawal, the addiction of the people will end. They will have to suffer, but Picard sees that suffering, no doubt, as something that should not be alleviated. It is an outgrowth of Ornaran and Brekkian choices, and so the two civilizations must contend with it. From that suffering will come growth, and change.
And who is Picard, or Crusher, to deny the people that change?
There are no phaser battles, new planets to explore, or very memorable aliens featured in “Symbiosis.” Instead, this is a portrait of a captain grappling with his morality, and the rules that he claims to cherish and live by. We see Picard agonize over this, and more than that, live with the ambiguity that he may never know if he made the right choice, or the wrong one, for these people. He does his best in the moment, even if Crusher disagrees with him. But Picard demonstrates why he deserves to sit in the Captain’s chair of the starship Enterprise.