Please see https://forum.syncthing.net/t/allow-disk-to-spin-down-even-if-paired-clients-are-online/19606. In sum, the only way would be to move Syncthing’s database to a different drive.
Please see https://forum.syncthing.net/t/allow-disk-to-spin-down-even-if-paired-clients-are-online/19606. In sum, the only way would be to move Syncthing’s database to a different drive.