When rolling back folder redirection, should I set it to Not Configured or unlink the policy?

I would not unlink it as the first step. A cautious sequence is to enable the option that returns folders to the local profile, give that change time to apply, then set the folder redirection settings to Not Configured so clients can process the policy removal. Unlinking before that change reaches users could leave some machines without the intended return behavior. Test the sequence with a small group before expanding it.

Also, don't judge the rollback just by how long it takes to reach the desktop. Moving a large folder back can make sign-in take a long time, especially when the data is on a remote share. Give users a clear heads-up, and check whether the move actually completed before treating a slow login as a failure.

For the machines that still fail, check whether Offline Files is involved. Cached folders or unusual ownership and access settings can interfere with moving data back. If only certain users are affected, compare their folder paths and permissions with a user whose rollback worked rather than assuming the policy change itself is the only difference.