Rear USB ports are not attached to the motherboard via trivially removable connectors. It also really is not trivial to chip off most types of even general-pur

Rear USB ports are not attached to the motherboard via trivially removable connectors. It also really is not trivial to chip off most types of even general-purpose epoxy with your finger on a flat surface, let alone a tiny USB port which your finger doesn't fit in. If the epoxy was selected with some level of care, it may be very, very time consuming, or nearly impossible to remove, even with the right tools. No matter what, it's a helpful measure in addition to every other way you can also disable a USB port.