I sold a statue this summer and customs USA decimated the art box. They cut the art & shipper boxes to pieces. The statue was fully insured. I worked out the dollar amount that he wanted back. I asked him to supply all pics (damage of box & numbers for statue too) to me and I submitted the current value; potential value and the amount I wanted refunded back to me so I can give it back to buyer. Doing all these time, there was a constant communication between him & I. He did file a PayPal claim (just in case in past the potection plan). After everything was filed, he got his money back.
Just a note, any items I sell, I take pics of it & how it's packed. I always add an additional shipper box (includes all original art box & ssc boxes). With the extra box it's either packed with foam or additional bubble wrap. The packing pics were also submitted to Canada Post.
I think as a seller, you need to take an extra step or precaution. But yes, insurance works in sellers favor.