ecryptfs has been removed due to questionable maintenance.
This following options are no longer be available:
security.pam.enableFscryptprograms.ecryptfs`
If you were using them, please consider moving to a move maintained alternative, such as fscrypt, gocryptfs or cryfs.
link to PR: ecryptfs: drop by Sigmanificient · Pull Request #479934 · NixOS/nixpkgs · GitHub