Super-Fast shipping is available now to everyone now via USPS Priority Mail 3 day. It's 3 days at most and unlike Amazon the delivery time is guaranteed. Amazon's shipping time estimates aren't trustworthy enough to rely on for important deadlines, the buyer has no recourse other than a refund if shipping takes longer than it's supposed to.

FWIW I would never trust USPS to deliver on time in my city. They regularly lose packages for a week or two before magically delivering them, with tracking information that is the long-form equivalent of ¯\_(ツ)_/¯. UPS, FedEx, and Amazon have all been vastly more reliable than USPS. However, USPS has been fine for me in other cities. Maybe, like real estate and cell phone coverage, location matters when it comes to package delivery.

BTW, when you say, "the buy has no recourse other than a refund if shipping takes longer than it's supposed to", do you imply that shipping via USPS gives you some other, more useful recourse if your shipping takes longer than it's supposed to? I cannot fathom what that would be, unless they're going to, like, refund your shipping and then give you $50 or something.

(Actually, if USPS was going to give me $50 every time they fumbled a package, I would ship everything USPS, always. I would order things I don't need, one shipment at a time. I would retire by the end of next year on my earnings.)

More specifically, Priority Mail Express comes with a money back guarantee where any delay would entitle you to a refund on your shipping fees.

OK, so that's the same refund of shipping fees you get from Amazon if they're late, right?

Actually, I've gotten free months of Prime with Amazon easily by just going into support chat and saying more-or-less, "You missed the guaranteed delivery date, I'd like a free month of Prime".

Of you are big enough, you want to be present on all large trading venues, say, both Amazon and eBay.

If this venue proves reasonably well functioning and promoted, big sellers will have to build their presence there, too, bringing in customers and more credibility.

It may depend on the value-proposition for the sellers. If Amazon takes too much of a cut, alternatives, even with fewer customers, may look attractive.

My guess is that Amazon will start banning vendors that also sell on Google.

This would almost certainly be illegal (antitrust violation) and probably wouldn't be worth the firestorm even if it was legal.

Amazon banned sellers from selling anything that competed with their firestick (Chromecast, Apple TV, etc ) for the longest time.

OK they'll raise seller prices and offer discounts for exclusivity.

Exactly. Or just lower vendor search rankings.

Will probably do nothing at least for now .. Google had the reputation to cut things that didn't grow as fast as it wants to, I don't even know for sure if Google Cloud will still exist in 2030.