Why would a free human society be in agreement on how to alter itself?

So I’ve been grappling with these discussions on the plausibility or implausibility of redefining cultural boundaries of several sorts to (as the radical example of self-alteration by Eliezer goes) make non-consensual sex as tolerated and tolerable as non-consensual conversation. Said discussions being quite separate from EY’s largely accepted underlying statement of principle; “Something in a world better than ours is likely to creep us out, at least purely emotionally.”

Then I suddenly saw a plot hole in the source material. The story outright mentions that internal disagreement was present at all points in its culture during the transition from 20th century sexual mores to the end result. So… why didn’t anyone who saw the trend of self-modification and couldn’t accept it for themselves or their children, DO anything about it? To use another locally popular example, if Gandhi knew that his children, whom he had begun to raise in pacifism, were to be given pills that’d make them enjoy killing in self-defense*, why the hell wouldn’t he and his followers split off? And, supposing that a large amount of Indians and others at the time disliked that slippery slope, wouldn’t their forked culture make a considerable impact on the future’s “mainstream” society, such as a much greater level of catering to pacifists in all areas of life than e.g. the visibility of Jewish kosher goods and services in today’s West?

In other words, why didn’t the story mention its (wealthy, permissive, libertarian) society having other arrangements in such a contentious matter—including, with statistical near-certainty, one of the half-dosen characters on the bridge of the Impossible Possible World? I strongly suspect that this blow to suspension of disbelief, while swallowed by most commenters who began talking about the implied binary choice (modify entire culture to tolerate rape/​society at large stays frozen in stone), added a great deal of needless, irrational controversy, fueling the already incensed emotions and such.

*(I know the real Gandhi didn’t totally abhor self-defense, but that’s beside the point)