While this diversity within the one Catholic Church can appear confusing at first, it in no way compromises the Church's unity. In a certain sense, it is a reflection of the mystery of the Trinity. Just as God is three Persons, yet one God, so the Church is 22 Churches, yet one Church.
The Catechism of the Catholic Church summarizes this nicely:
"From the beginning, this one Church has been marked by a great diversity which comes from both the variety of God's gifts and the diversity of those who receive them... Holding a rightful place in the communion of the Church there are also particular Churches that retain their own traditions. The great richness of such diversity is not opposed to the Church's unity" (CCC no. 814).
Although there are 22 Churches, there are only eight "Rites" that are used among them. A Rite is a "liturgical, theological, spiritual and disciplinary patrimony," (Code of Canons of the Eastern Churches, canon 28). "Rite" best refers to the liturgical and disciplinary traditions used in celebrating the sacraments. Many Eastern Catholic Churches use the same Rite, although they are distinct autonomous Churches. For example, the Ukrainian Catholic Church and the Melkite Catholic Church are distinct Churches with their own hierarchies. Yet they both use the Byzantine Rite.
To learn more about the "two lungs" of the Catholic Church, visit this link:
The Vatican II Council declared that "all should realize it is of supreme importance to understand, venerate, preserve, and foster the exceedingly rich liturgical and spiritual heritage of the Eastern churches, in order faithfully to preserve the fullness of Christian tradition" (Unitatis Redintegrato, 15).
A Roman rite Catholic may attend any Eastern Catholic Liturgy and fulfill his or her obligations at any Eastern Catholic Parish. A Roman rite Catholic may join any Eastern Catholic Parish and receive any sacrament from an Eastern Catholic priest, since all belong to the Catholic Church as a whole. I am a Roman Catholic practicing my faith at a Maronite Catholic Church. Like the Chaldeans, the Maronites retain Aramaic for the Consecration. It is as close as one comes to being at the Last Supper.
My recollection from reading years ago is that priests werent allowed to marry because in ancient times they would establish churches in remote places that might rarely be visited by church authorities. If the priests married then the churches might be claimed by heirs as their property and the church would lose it. (Dons protective clothing and hunkers down.)
Probably the best thing would be for the Vatican to offer a similar deal to what it does for married priest Anglicans who convert, likewise treated on a case-by-case basis.
This does not surprise me, since now the Latin or Roman Rite now has an Anglican usage rite which accepts married priests. It was bound to happen.