Things Fall Apart is a tragedy, made so by Okonkwo’s hubris.
Okonkwo builds himself up to be someone who is strong, weak fearing and entirely masculine. He rejects everything that is soft, and in doing so he repeatedly shoots himself in the foot.
In being against femininity, he is abusive to his wife, and their children.
He kills his own adoptive son, and in doing to is cast away from his home.
In rejecting colonial influence, and having been rejecting his own blood related son Nwoye, Nwoye leaves him to join the church.
There is also anticolonial themes in Okonkwo’s rejection.
Okonkwo’s rejection of the gentleness he saw in his father, has caused every issue up until his suicide, and indeed, his suicide also.