Grossberg is wrong on almost every point. eBay is not Amazon and never will be for one simple reason - eBay is not the seller. On Amazon they are the primary seller and all other sellers are secondary. Even to the point that a seller must use Amazon's payment system to process payments. I would almost be willing to bet that Grossberg's sales are not anywhere near the volume of his eBay sales and never will be.
The community spirit is what made eBay what it is today and the move away from that model is what is causing all of eBay's problems. Powersellers by the dozens are leaving eBay due to its move to attracting large sellers via false feedback, low or no listing fees, and lowered final value fees. They are protecting the large volume sellers at the expense of the small sellers and it is causing both traditional eBay sellers and buyers to go elsewhere.
The one point I agree with him on is the flawed feedback system. It worked best when both the buyer and seller could leave positive and negative feedback. Even as a small seller my NPB strikes have increased from one a year to several dozen. Fortunately I have not had a negative feedback yet and I believe eBay has made changes to remove negative feedback left by NPB's.
E-mail over load - while I have not looked at his listings I would be willing to bet his ads are inadequate, his policies are poorly defined, and his follow-up emails are either non-existent or poorly written. Even as my volume grows I have had very little email from buyers. Most of it is offers when I use the buy it now or best offer option.
For the sake of eBay's future I hope they do not listen to Grossberg and return to the original eBay model. Until they have their own inventory and are actually the seller they will never be Amazon. I have sold on Amazon and I know their policies are more rigid, the return policy more restrictive and their control over shipping prices can be very difficult to deal with. Not to mention that if you have a unique item, write a product description, have it approved by Amazon then every other seller who comes up with the same product gets to use your description. Branding is very difficult with Amazon.
Bring back the old eBay and do away with the volume sellers or at least level the playing field, and you will see eBay rise from the ashes of their own fire.