Are puzzle toys safe to leave with an unsupervised dog?

This is the most consistent safety flag in the threads we read. Several high-trust r/Dogtraining and r/dogs commenters specifically warn that plush and removable-piece puzzles are not safe to leave with strong chewers unattended, and that destroyers can shred a mat in a single feeding. Reviewers broadly recommend supervising puzzle play and choosing harder-wearing options for power chewers.