there are ways to easily deal with fridays child and errand of mercy.
that other species, civilizations, traders made earlier contract with the people on both planets before the federation got to them.
we know with errand of mercy there had been earlier surveys of the planet. spock mentions how contradictory they seem at different points in the story.
the same situation also seems to exist in fridays child.
as for return of the archons and apple there could be a dispute if the planets culture had already been hurt by the supercomputers running them.
what is interesting in both cases after enterprise left kirk dosnt just leave the people without help.
but rather leaves behind teams of different experts to help the people make the transition.