"...2) also, if you are one of eBay's most reputable sellers that consistently delivers outstanding customer service, there should be no option for negative or neutral feedback."
Being a top-rated seller is not a guarantee for buyers that every seller will manage perfect performance on every transaction.
And actually, the feedback system's purpose has changed pretty drastically from eBay's early years. Then it was a necessary report of a trading partner's honesty and reliability in the community of buyers and sellers. Then there were fewer safeguards for buyers than there are now. These days feedback is not as important, and fewer people are leaving it and consulting it. It still has some meaning, mainly for buyers to vet their sellers, but it is waning.
Now there are strong buyer protections as well as specific seller metrics to keep the eBay population safe, and feedback is no longer factored in to those metrics. It is too subjective and arbitrary, and therefore not always a reliable measure. So it would not be useful for sellers to use feedback to report bad buyer behavior, for the same reasons eBay no longer uses it to judge seller performance. There was too much abuse of the process, with some trading partners leaving unfair dueling negatives and retaliatory comments, subverting the feedback 's purpose.
Instead, it is now far more useful to give non-paying buyers a strike on their account as opposed to leaving some comment in feedback few will see. The no-payment strike helps all sellers savvy enough to set their Buyer Requirements, compared to a follow-up comment in feedback that most sellers would not see til after the fact (as most buyers are anonymous until the transaction takes place). So there would be no opportunity to read a buyer's feedback prior to the sale, even if eBay allowed sellers to leave negatives for buyers.
