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This question and answer very much relates to the question of apostasy, which was so brilliantly highlighted by this insightful gentleman.
I admit to having fallen in the "progressive Christianity" trap prior to a painful but enlightening series of reality checks.
The popularity of progressive Christianity, in my experience, is enabled by general ignorance of Scriptures and a kind of spiritual laziness that feeds the disconnect.
As much as we can't attain physical fitness without exertion and proper diet, we can't attain spiritual fitness without exercising our eyes and minds the word of God; attending a bona fide Christian church for worship; associating with other Christians for fellowship, sharing and assurance, and being always ready and willing to witness, serve and defend the truths of Christ and God's love, power, grace and existence.
Adhering to this spiritual fitness regimen aids in our discernment or truths, and helps us dismiss and avoid the pop cultural trends like progressive Christianity, and other organized beliefs that splinters us and marginalizes our Christian faith.
"Progressive" is more regressive and revisionist that is nothing new, and certainly not more insightful. On the contrary. Progressive movements are nothing more than collective excuses for personal preference, whims and notions; qualified disobedience, doubt charading as high intellectual functioning; and overall a growing clique built on enabling immaturity and moral lapses.
(Again, please read the answer on apostasy.)