Pity that Picard had interfered, if it weren't for him the Feds could have just removed people from a planet on which they didn't belong anyway and taken for themselves what they wanted.
You know that "never ask when you can take" is a Ferengi and not a Federation rule, do you?
Would I have pursued the move of the Ba'ku the way the Federation did in the movie? No
Would I have moved the Ba'ku? Yes
And meta-phasics are only a minor reason for it. What happens when other species catch wind of the fountain of youth?
You really have three choices:
Move the Ba'ku.
Protect the Ba'ku.
Or declare open season on the Ba'ku.
Both moving and protecting the Ba'ku have Prime Directive ramifications. But moving them costs nothing in Federation lives. How many Federation lives are you ready to lose if someone wants to take meta-phasics by force? Declaring open season on the Ba'ku only ensures they die a bloody, pointless death.