Likely because the fundamental difference between the male and female deacons was commonly understood and unquestioned in ancient times, the Church was free to use imprecise language that would become confusing in modern times to people who do not commonly understand that women cannot validly receive the sacrament of holy orders. Analogously, in medieval times, the blessing given church bells was popularly called “the baptism of the bells” although no one really believed that the bells were given the sacrament of baptism. Only during the Reformation era did Protestant controversialists begin to misunderstand the blessing, although they did not also misunderstand the practice of “christening” ships.
Now that there is widespread misunderstanding of the nature of the sacrament of holy orders, the Church is especially careful and precise in its sacramental language and would no longer refer to female assistants to the clergy as “deaconesses.” What was once an unobjectionable term because it was properly understood can no longer be used because it is now open to confusion.
