I do believe sin is one of the two factors in play here. But not just sin necessarily, but the allowance of it within the church.
It's not that churches should cast out people who have sinned, far from it. But it should be preached constantly that Christ died to free us from sin, not to provide us a cover to go on sinning and say "I'm a sinner saved by grace."
God makes no empty promises. He never once tells people to do something without then giving them the power and ability to do it.
Be holy as I am holy! That is a charge that seems impossible on face value, but he gives us his Holy Spirit to dwell within and empower us to do the impossible.
I see and hear this every week in my church. "But as long as I'm in this body I will just continue to sin." That's not the point, the point is God calls you a saint, he charges us to be holy. Stop with the infatuation with sin and actually trust God to do what he said he would do. Actually crucify the flesh, then stop declaring "Flesh come forth."
Until believers stop compromising with sin, power will be limited. God is still so gracious and gives us tiny glimpses of what he can do. But to the ones who go all out, fully committed, fully invested and fully led by the Spirit, there is literally no limit to what God could do through that person. But the compromising has to stop. We must hate sin as God hates sin.
Amos 3:3 Can two walk together, except they agree?