"Backsliding" refers to believers turning away from what they think is the will of God and perhaps doing something else, but certainly not doing according to their understanding of God's will.
We all sin, in act and deed or omission of deed, whether or not such "sin" has consequences or not due to the Blood of the Lamb.
Thus we all backslide to a degree.
The issue is do those born anew ever stop believing Jesus is Savior and Lord? Does their faithlessness extend that far? My answer is No. I believe our core faith is protected by the power of God, 1 Peter 1:3-5
But the bottom line is we are to evaluate our walk with Christ and strive to return to His path, so as to "pick up our cross and follow Him.
Great OP devotional!