Fascism, traditionalism, neo-monarchism, authoritarian forms of socialism, and theocracy are all very real and have both adherents at home and entire societies abroad that attempt to live by their rules. Unfortunately all of them yield a society that is worse in many important respects than Western liberal capitalism. They are stifling, repressive, or lead to poverty. The domestic adherents of these ideas tend to be either angry nihilists and edgelords who hate their own lives and just want any kind of change, or fanatics (e.g. religious zealots) who are obsessed with controlling and restricting the personal choices of others.
There are also lots of pure fantasies that are pushed as alternatives to capitalism: neo-primitivism, hand-wavey futurist utopias, new age woo, etc. While these may or may not be better, the point is moot because they are not achievable. There is no path from here to there, or in many cases there isn't even a "there." There's just a vague idea that if we all abandon what we have now and love each other or something magic will happen and we'll get utopia. History shows us that without a real serious workable plan we're more likely to get a slum run by warlords or a new boss that's worse than the old boss.
If someone thinks of a serious alternative to Western liberal capitalism that is both better and achievable (there is a path from here to there, and an actual "there"), I think they'll get plenty of attention. There is no invisible conspiracy that will somehow stop people from thinking of this or discussing it. It's just that nobody's done it yet.