I remember someone told me: "the entire community of true believers in Christ regardless of their religious affiliations [e.g. Lutheran, Evangelicals, et al] is the genuine Catholic Church..."
MY REPLY: "catholic" or "universal" church was used by the Early Church Fathers [particularly St. Ignatius of Antioch; c. 1st century AD] to distinguish the then infant CHURCH from heretical churches having an array of contradicting doctrines and labelling themselves with the name of God, Jesus Christ or the apostles to appear that they are legitimate apostolic assemblies of believers (as it has been the case from then until now).
Wherever the bishop appears, there let the people be; as wherever Jesus Christ is, there is the Catholic Church. It is not lawful to baptize or give communion without the consent of the bishop. On the other hand, whatever has his approval is pleasing to God. Thus, whatever is done will be safe and valid.But we must insist that this word is not only implying UNIVERSALITY but also UNITY [cf. Jn 10:16, Rom. 12:5, 1 Cor. 12:13, Eph. 4:4-6]. It refers to the ancient faith "that has been believed everywhere, always and by all." It pertains to the ONE TRUE FAITH [cf. Eph. 4:5] which is once and for all delivered unto the saints [cf. Jude 1:3]. It expresses ORTHODOXY, HARMONY and complete UNION within ONE BODY OF CHRIST.
— St. Ignatius of Antioch [death: c. 107 AD]
Letter to the Smyrnaeans 8, J.R. Willis translation.
Now, do protestants and other "christian" denominations have such CATHOLICITY in the correct sense of the word?
Your guess is as good as mine. :)