Ebay should directly accept bitcoin payments and then it would be good enough as PP can be charged back but not bitcoins. Their split up with PayPal has not made a significant difference as they only offer that payment option for US goods. For Indians they do have another payment option paisapay but that's also not good enough.
but if they accepted bitcoin payments, how would that affect buyer/seller protection? people can and will lie to save every penny they can; chargeback scams already happen often enough on ebay.