Isn't that a central premise of Star Trek? That indeed, VAST numbers of humans actively FLEE the Federation for lives that are much-much harder and often following strange ideologies?
* The Masterpiece Society
* All of those rugged settlers that occasionally include people like Ezri's family or those criminals Miles o'Brien lives
* The people who left the Federation and became the dystopian hellhole that tasha's family are from
* That Luddite commune mentioned briefly in DISCO.
I mean, the whole point of the show is there's humans in paradise and humans seeking something else.
For me, the fact Maurice shuns technology and his wife does to is the easiest explanation why they don't get her treated.
Correct, but we didn't see that Maurice and Yvette completely shunned technology. They lived a very low tech life it seems, so, would they really opt to not get medical treatment for something like this?