It's kind of ridiculous to say that life under Cardassian rule was the same as the prior Bajoran way of life. They dominated their entire economy and stole all their resources, not to mention that they stole the orbs which are their primary resource to contact their Gods.
To establish whether this is ridiculous, we'd first need to know who held those resources before the occupation. Was there a difference between the economy being dominated by the Cardassians and the economy being dominated by the Bajorans? Was there a difference between the Orbs being on Cardassia Prime and the Orbs being in the secret basements of monasteries? The place doesn't appear to be a representative democracy, and is more like a theocracy for all practical purposes; the "actual Bajorans" would have been "dominated" in any case anyway.
Culture is not a static thing that needs to be preserved in a jar. Culture is fluid.
Not Bajoran culture, apparently. It's more ancient than anything in the human sphere of experience, and supposedly extremely stable. It doesn't take any preserving by outside agents - it stays immutable on its own.
Bajor continuing out into the interplanetary community as equals is the natural development of their culture
Sure.
and forcing it to stay static at the end of a chain would have destroyed it.
Probably not. After all, staying static is what it had been successfully doing for the past twenty thousand years or so - and that's just a fraction of its total history (and never mind prehistory).
some practices that are clearly wrong
No such thing for
Homo sapiens. We have tried it all, and there simply is no agreement on what is good and what is evil. There are local standards that sometimes are at extreme odds with each other - but picking the "good" out of any two is for the stronger, more oppressive party to do.
Of course, the DS9 story is particularly telling because both sides to the domination game are alien to us - and this is of course achieved by creating specific fictional nonhuman characteristics for each side. Although they aren't developed much, because the writers are hard pressed to understand what "Cardassians value family more than humans" might mean in dramatic practice. Yet in essence, we are watching from the outside, collectively representing the "human point of view", which of course is pure fantasy, as humans cannot agree to a point of view. It's fun to project one's subjective morals to the story, but the actual lesson to be learned there is that morals indeed are subjective, no more substantial than those created by a science fiction writer for entertainment.
Timo Saloniemi