I  have contacted ebay regarding their continuing draconian attitude toward sellers . They never replied.

 "Unfair postage and packing charges"is now  determined by your dear buyers, who may have bought a perfectly well described Ikea chair which they had convinced themselves was  a Chippendale.
Disgruntled buyers now have a chance to snipe at sellers whilst disguising their attack as "positive' feedback. they can damage the seller leaving an emaciated galaxy of stars.
This Parthian shot from the buyer can have severely deleterious effect on the seller.
I have weighed books and calculated the postage at cost only to be told by a buyer
 " You are trying to rip me off." But, I was not. Books are heavy, postage is dear, insurance costly.
Scenario:
 Buyer buys a piano for £400. ( secretly hopes it is a Steinway)
It is not- he is gutted!
Thinks: Star Wars! I'm gonna get 'em!
He can be unreasonable or even malevolent.
He is angry but sly. He doesn't want to damage his own feedback so leaves a hearty positive ( so he gets one back!) but also with a load of nasty  mean little star strikes.
Your communication was crap- I star
Your postage was crap- 1 star
etc
 Buts secretly the truth is:I expected more than I got - you will pay for my folly!
Or maybe he has no idea how much postage costs!

Ebay has not taken into account that buyers can be small-minded, naive and aggressive.
Ebay does not  appear to care about the sellers, because it has been accused most publicly of scams.
The real scams are perpetrated by small time crooks and can be carried out against sellers as well as buyers.
I am unable, as a seller to find out who thought my postage charges were excessive and why.
I am led to withold feedback for buyers and closely monitor my stars like a jealous mother.
Ebay administration have introduced a very unfair, undemocratic system.
Also- the planet is dying. Do you really want to receive your goods in a nice shiny packet? or would you prefer your seller to recycle an old one?
Are you going to penalise the seller for recycling by leaving a mean star rating?
Are you a narcissist? A fool? A meany?
Ebay is hard work. I have a damaged shoulder from carrying parcels. Nevertheless,  I try to send out ON TIME, EFFICIENTLY and POLITELY.
Ebay- stop treating sellers as though they are the enemy. The enemy is greed- and avarice.