You will find it difficult to file a class action suit because
1. it requires finding a judge who will override the arbitration clause in your agreement with Ebay
2. Because it will be hard to find a lawyer who will accept your case on a contingency basis since the risks of the result you had would have been known to most if not all prudent sellers.
Under consumer protection laws, you are responsible for the safe delivery of your orders.
Insurance is a way of protecting yourself if the shipper you used fails to deliver.
You are paying the Ebay fees because you did not resolve the problem with the buyer and Ebay was called in.
Clearly, you have little experience as an online buyer or seller and chose to sell an expensive, heavy item.
Selling online is not an easy way to make some money, no matter what some Youtube video might tell you.
You should never sell anything online unless you can afford to lose all of it and more. You should never expect quick cash. And Murphy's Law often applies - anything that can go wrong, will go wrong.
Your experience is not out of the ordinary, but you could have lessened or eliminated some of the risks had you done more research on how to sell online.
