I don't agree that "good people" would want to help the Baku. The Baku showed every sign of being selfish, self-absorbed, and closed-minded.
I see nothing of that in the film. They weren't even asked. They were spied on, they were lied to, they were attacked, and then they were about to be murdered, all for a luxury item that, in the wrong hands, can also be greatly misused.
I personally value life over luxury resources.
The Ba'ku are portrayed like the Amish, which is a choice of lifestyle I respect. If you want to live a life with all the pleasures of technology and modern society, you are free to do so, but you may not return. AND the Ba'ku DID NOT
exile them from the entire planet. That is explicitly stated in the film when Picard talks to Dougherty in his ready room. That was the Son'a's choice alone, because they "didn't want to live in the Briar Patch".
The Son'a wanted to have both the cake and eat it, too, and were ready to harm others for that.
They tried to kill
Data as soon as he discovered the holoship, and they again tried to kill
Data and Picard as soon as they rediscovered it. That's how secret and illegal
the whole plan was.