The current situation is screwing a small number of unlucky consumers, but providing a net benefit for the overall aggregate of consumers, due to lower prices and fees.

What your proposing is to screw consumers overall in order to provide fairer treatment for the unlucky few due to ebay having to charge much higher fees in order to cover the cost of fraudsters.

Since buying and selling goods and services online is not a constitutional right, or any right anywhere as far as I know, a proposal to force such a change does not seem like it will pass muster in a serious court of law.

I'm not a lawyer but even to my untrained eye you will need far better arguments to get any traction.