If they had phrased this as "we have decided to drop them because the DDOSes they were experiencing were more expensive than the money we were making from them", would you have been ok with them dropping them? Or would they be required to publish a hard rule about 'we will drop a customer that experiences more than x amount of DDOS traffic'? And if they have to do that, that is basically telling adversaries, "DDOS us this much and you can get us dropped"

It seems really tricky to make this a rule that businesses have to do business with everyone. It is a very established rule in the United States that a business is free to enter into business agreements with whoever they want, as long as they don't discriminate based on specific protected classes.

If you want to censor someone, just censor them! Trying to come up with PR gobbledygook to make the action seem less bad is lame as fuck.

That said, your actual argument about "cost" I reject. Infrastructure providers should be required to service everyone, even though some cost more than others. Indeed, that's the whole point—imagine if AT&T didn't have to handle phone service for the whole United States, and instead only did more profitable, cheaper urban centers?

I'm more than willing to pay a small amount more so that everyone is treated equally. That's just part of living in a society.