Why not just use the 600 other things they have that can do that.
I mean metaphysic particles are kind of pathetic next to technology that can raise the freaking dead.
We don't know how reliable and consistent those "other ways" are, there does seem to be a reluctance to employ them. Nor how acceptable they are to the majority people of the federation membership.
Sure federation medical science can give Picard an artificial heart, LaForge a visual scanner, and Neelix one transplanted lung. But in terms of a more natural treatment and a holistic medical approach, the particles would be more in line with that.
The fact of the matter is after Picard had his heart destroyed in a fight, Starfleet choose NOT
to put him through a transporter to repair the damage. Nor did Nog get his leg fixed in short order. Nor did Picard's brother and nephew get brought back from "the freaking dead."
You might be seriously over estimating what therapies are generally available in the 24th century.
People still require natural occurring drugs that only come from a single source, and that would include the particles from the ring planet.