SammyBoy has said it best, although I know there will always be a minority of buyers who'll accuse cautious sellers of "feedback extortion."
I feel that (ideally), the feedback system should ALWAYS have been constructed this way.
But I know many wonderful sellers who have been deliberately targetted for harassment & negative feedback by individuals with multiple shill accounts (one famous shill maintains over ONE HUNDRED accounts!) designed SOLELY for this purpose.
They harass a seller, never pay, leave a negative.
The seller blocks them as bidders, but they just attack under a new ID.
Again & again.
eBay once had auction options that protected sellers from these disturbed individuals, but these have been gone for some time.
And with this new (theoretically good) feedback policy, sellers are even more vulnerable to these psycho-buyers.
While targetted sellers can often get such feedback removed, the time & energy lost - and the damage done - is profound.
Stacey, if you'd experienced this, you'd understand why your "feedback extortion" stance is an incomplete view.