Doctrines not affected by modern Bible versions?

Supporters of modern textual criticism, the Modern Critical Text (MCT) of the New Testament, and the modern Bible versions translated from the MCT, often assure us with the claim that although the MCT is shorter than and significantly different from the Textus Receptus (TR) - the traditional Greek New Testament text handed down faithfully by Christians from generations to generations throughout history, no major doctrine is affected. In other words and by extension, the MCT supporters are claiming that no doctrine and no understanding would be affected if a man reads a modern English Bible version translated from the MCT such as the ESV, NIV, NASB, and CSB instead of the Authorised Version (KJV) that was translated from the TR. 

However, the claim made by MCT supporters is false. Two major doctrines are immediately affected by the acceptance of the MCT. 

First, the Divine Preservation of the Holy Scriptures. If you accept the MCT, you would be saying that God did not preserve His Word because the supposedly true New Testament text was hidden from Christians for 1,400 years and therefore, during that 1,400 years, Christians did not have the true New Testament text.

Second, the infallibility of the Holy Scriptures. If God had not preserve His Word, how can we be confident that the Bible we hold in our hands is the infallible Word of God?

When these two major doctrines are affected, the authority of the Bible in the eyes of man would also be affected. If man has doubts about the truth of the Bible and no longer trusts in the Bible, potentially ALL doctrines can be affected.