In Things Fall Apart, the Igbo culture was one of the few remaining parts of indigenous African that was insular, self-governing, independent, and segregated. The tribe was a collective of nine villages which acted like its own city-state: it did not need outside resources, technology, or immigrants for sustainability. In fact, the Igbo guarded themselves heavily against outsiders, as evidenced in the killing of Ikemefuna (he was an outside threat to their identity). They also committed infanticide against twin babies and other outcasts.
It is ironic that the tribe was not as threatened by the establishment of the Christian church. They were tolerant only because they thought, because the church was built in the evil forest, that the missionaries would be haunted and driven out by evil spirits. So, superstitions gave them a false sense of security.
In terms of agriculture, they would certainly be put out of business. They had no concept of land ownership. Even though most yams still come from Nigeria, it would be doubtful that their crop system could sustain the community. Mass production and government intervention likely would end the ancient farming practices of the male yam farmers.
It is important to note that the Igbo were integrated and holistic in terms of their religion, economy, education, and legal system. All of these elements were practiced by all, openly, within each village. They did not have the Western institutional separation of church and state. Ultimately, institutions are what do the culture in most: religion (the Christian church) and the legal system (holding the male elders in prison). The culture fell apart after it was exposed to the machinery of specialization and segregation of institutions.
All this is to say that the tribe would not fit in in the 21st Century globalized world. Not only did they lose cultural identity in the 20th Century colonial world, they would certainly even be more overwhelmed by today's pluralistic, highly scientific, gender integrated home and workplace (women as same status as men), and highly mobile society. Their agrarian, sexually segregated, and male dominated collective would certainly become taboo and obsolete by today's globalization.