I'm glad you've never had to do a charge-back, or dispute a charge to your account. Unfortunately, not everyone's had such a pleasant experience.That's beside the point. You claimed no one would buy if not for availability of chargebacks. This is simply not true, not because I did not ever do a chargeback, but because I never even considered whether I can chargeback or not before performing a transaction. I doubt I'm in any way special in this, so there definitely are people who would buy even without the chargeback option.
What happens, for example, when an up-til-now reputable seller takes a ton of order money and bails(a pump-and-dump scam)
You lose some money, they must close their business. You and the other screwed customers report the case to the police. Just as in any other fraud case?
it's the seller who's more trustworthy than the buyer. Why is that?
Because a vast majority of transactions are between a user (buying) and a company (selling), not two users. Which one do you think is more trustworthy, a random amazon customer or amazon?
All of your points put so much control in the hands of businesses.
No, they put some control in the hands of the seller, making the situation more fair. A seller and a buyer still can arrange a transaction that's safe for both based on bitcoin. That's simply not possible using paypal, because there is no way to prevent the buyer from taking his money back.
Where do they go for help? Bitcourt?
Where does the seller go for help now when a buyer charges back? Paypalcourt?