There is a presumption that the first Christians were closer to the original intentions of Christ and the Apostles than people living 20 centuries later, and were, therefore, more likely to be correct as regards doctrine and religious practices.
But that's not the whole of the picture. The Bible is a record of the first Christian churches as well as the teachings of Christ. No amount of being close to the origins of the religion would settle this matter...if the word of God were not also in accord with the practices we are discussing.
On that score, the Bible is almost totally on the side of an all-male clergy. Consequently, the Christians of our time who want a change because society has changed around the church have almost nothing BUT that argument (society has changed, so the church must adjust to it) to offer in support of their position.