Is it damaging to drain an Eaton HS Supercapacitor below its minimum working voltage?
Eaton HS model is not a regular supercapacitor, but it is a hybrid supercapacitor.
It is a hybrid of regular supercapacitor and lithium-ion cell.
So same restrictions apply due to the lithium-ion cell technogy - the lithium-ion part of the hybrid capacitor will get damaged when it is discharged below safe voltage.