Even setting aside that Ukraine never had the technical means or infrastructure to operate/maintain those weapons, I don't think they would have dissuaded Russia or actually been used. Russia could turn them into a wasteland in response and 6 million people (including hundreds of thousands of men of military age) weren't even willing to stay in Ukraine, much less fight for the country. If Zelensky were to give an order to launch hypothetical nukes, I'd think there would have been a coup and no launch.