There is much more evidence of the extent of early missions. A Japanese professor P.Y. Saeki stated that Nestorian Christianity penetrated the whole of Chinese literature and that Asia was widely covered by missionaries. The Nestorians were an eastern branch of the church, which went out mainly from Persia (Iran).
Most of the world was reached in the first millennium. Australia and America are left out of this study. Leaving aside the theories of evolution it is doubtful that their populations were extensive. We need an anthropological study of migrations to show this. Philip Nicolai (1556-1608) claimed that European explorers to the Peruvians, Brazilians and West Indies found evidence of earlier Christian witness.
The Great Commission is not complete: it goes on in every generation. But this shows what a tremendous job the early church did. In the midst of persecution and heresy the European church dominated the continent by the 5th Century. The Nestorians, despite their humanism, made unbelievable strides and were highly dedicated to their task.
God does not require satellites and aircraft to fulfil the Great Commission. Current generations are not more able than past. We should use technology, but it is the gospel that is God’s power and God who makes His people willing in the day of His power.