Perhaps you ought to explain what you mean by appropriation in this particular context. Given the way you introduced it, you suggest that it counts as "doing it wrong". Is this always true, even in SFF**?
** - For instance, in a far future, might what we see as a mistake in describing a culture that exists in our own time merely be what that culture (or aspects of it) have become in that far future. (And if there is a "dark ages" problem in that future world - i.e. a lack of information about our time - wouldn't mistakes and misconceptions about all our current-day cultures be natural and, indeed, expected?)
"appropriation" is a word used in postcolonial theory (and often by feminists, critical race theorists and others as well) to mean the claiming ownership of "cultural stuff" that's "not your own." it's an incredibly vague term, open to a lot of interpretation. but i think it's useful as well if you are specific about what it means. for me cultural appropriation means taking something you don't have experience of, claiming it as your own and then misrepresenting it by dumbing it down.
like, what if someone set a story in africa when that person has never been there and doesn't actually know any africans? problems are likely to arise. characters are likely to be inauthentic, and very possibly based on stereotypes; places are going to look, sound and smell wrong, so to speak. actual people from africa who read the story may be horrified to find an alien world, while a lot of the non-african readership may think it's "really real." a major criticism of bacigalupi's
the windup girl, that has been articulated elsewhere, is that his thailand is inauthentic, but a lot of readers, critics and awards people lauded its "authenticity."
for some people, though, appropriation has a broader meaning: any instance where white people write about non-white people, or first worlders write about the developing world. i do not agree with these kinds of definitions, because the who concept of "ownership" is deeply problematic. i mean, should british writers avoid ancient greece because they are not greek, even though ancient greece is the root of ALL western civilization? should a british writer who lives in singapore and has for most of his or her adult life not write about singapore, even though he or she knows it much better than britain? no, of course not.
for me it's all about how you do it. i also think if you are writing about a place that's not commonly represented in SF/F, you also have a sort of special responsibility not to caricature it or end up just perpetuating/reinforcing stereotypes about it--something that can happen unconsciously.