As has been pointed out by a number of people celibacy of the priesthood is a discipline and can be changed. What I believe would happen if the discipline changed:
Down the track a priest would divorce or be divorced - the media would love that. A child of his would take drugs or commit a crime - the media would love that as would the scandal mongers. "How can he give us advice when he can’t keep his kids in line? "
People would wonder if he tells his wife the sins confessed in confession.
More money would have to be raised from traditionally stingy Catholics to support the priest and presumably 6 or more children. Maybe the priest could have advertisements on his chasuble or on the walls of the church.
If a priest didn’t have at least 6 children people would wonder if he was contracepting and whispers would start.
It would be very difficult to move a priest to a different/difficult or remote parish because of the cost to the family in terms of friendships and schooling.
Daily Mass could become a thing of the past. The Eastern Orthodox clergy don’t celebrate daily Mass because the priest may not have conjugal relations with his wife the night before the Divine Liturgy and I am presuming that the Latin Rite of the Catholic Church would follow that custom.
These are just some things which occurred to me.