The Q are definitely not a pre-warp civilization, so I doubt it applies.
But doesn’t it? She is an evolving Q. What right does he have to get involved? He’s just being a busy-body.
That female helmsman changed her hair since last episode.
I notice these things.
Okay. But was it ever established that the Q have any non-interference policy?
She’s a Federation citizen, though. I think he’s well within his rights.
She just changed a whole eco-system. That’s gonna cause so many problems. No?
“I hope I can come back and see you.”
“You’re a Q! You can do anything you want.”
Then apparently she never wanted to see you again. 
Indeed. I think on the last podcast they were mis-interpreting the Prime Directive a bit. Applying it to DS9 A Pale Moonlight didn’t make any sense to me.
“You’re a Q. You can do anything you want.”
Even though Picard will scowl at me.
What Would James T Kirk Do?
This episode wouldn’t exist because Kirk would have destroyed Q back during Encouter at Farpoint. Kirk doesn’t toterate god-like beings or omnipotent computers.
She changed it back to its natural state before the industrial accident that polluted it. Probably the worst effect will be destroying the profits of the companies that make those inhalers.
Now that she’s a Q she’s above the law. Outside the law. She’s a Men in Black.
There’s no money in the 24 th century you silly head. 
There is a bit of a difference between non-interference and the Prime Directive. The Prime Directive is a an ideal and a suggestion, IMO. Non-interference is a choice. A decision to not get involved or manipulte a culture, people, political situation, etc. if you have the technological and supieror means.
Actually, come to think of it, this episode comments on this arc effectively. You have a super powerful alien race and a morality play. This is all up in the non-interference.
DS9 wouldn’t ever have any contact with a pre-warp society. It was a space station. How would they even meet other races without warp?
WWJTK?
Kirk smacks her while she’s being hysterically indecisive and then kisses her while holding her shoulders hard. She decides it’s better to be human but relapses, saving the planet in the process. Now fully Q, Kirk is forced to kill her, because gods don’t need starships.
Not in the Federation. Elsewhere, though…
WWJTKD?
At some point he would grab the young girl by her biceps and pull her close while saying emphatically, “You can be…anything you want. You can do annnyyyyything you want. But you have to make the choice. It is your choice.”
Then some stuff happens.
Finally, Kirk emotes on the Bridge, “Q, this girl can teach you a few things about what it means to be human. Maybe you’ll even become a person, instead of a jerk. Now get off my bridge!”
Q exits. Laughter ensues.
But what about all the living things that adapted to that environment? Wouldn’t such a sudden change have drastic effects?
LOL! I like yours better than mine.
Te he he. I like yours better too. I can totally see Kirk saying those lines.
Okay. I buy that. That’s valid.
Yeah. Which is why —even though DS9 was SO well done — DS9 can never be my favorite Star Trek.
I won’t be pissy about it and say it isn’t real Star Trek. But to me, it’s a sideshow. A good side show. But a side show.
I look at it like the Gulf Oil Spill. If it was suddenly cleaned up, even the fish and birds that were managing wouldn’t be too upset to go back to the way it was before.