No disagreement with that.
I don’t see that the one necessarily has to do with the other, however.
One can fall away without losing one’s free-will.
Correct,...and we do.
There is another important aspect of volition in the Church Age. In order to be forgiven righteously AFTER we sin, by our volition we must face Him, and confess our sin to Him.
The reason for bowing our heads when we pray is privacy, not piety. In the privacy of our thinking, focusing on God and what He provided on the Cross, we are able to faithfully communicate with Him. It is still possible to pray to Him, but imagine how that prayer might be interrupted by a gang of grade-schoolers running around the sanctuary as you pray, playing games, being obnoxious, rude, inconsiderate, and insulting, attempting to divert your thinking towards them.
If these things are human caused, then it would be akin to such behavior and violating the privacy of the person seeking God. It also would infringe upon the protocol He has established between Him and the individual believer.
If the out-of-fellowship believer were unable to pray to God per 1stJohn 1:9, he would remain out of fellowship. If this occurred on a wide scale attack, it could result in a Great Apostasy.