AFAIK personal liability is something like when someone comes to your house and slips on a puddle you have on the floor and hurts themselves and then sues you. It's not about damage you did yourself, on purpose, to the property you rent from someone else or someone else does on purpose against a property you rent out.

All the insurance policies were about accidental damage on either side.

Then why would an apartment require you to carry it and list them as the interested party? What would they care if it just protects you against drunk partners at your place that get injured?