[andrewflnr]

Ok, that's good to know. But I still don't see how having congestion control be driven by receivers instead of senders makes it harder to fix than it is currently.

I mean, I don't actually see why you would need more ports at all. You still just have a certain number of machines that want to exchange a certain amount of traffic. That number is either above or below what your core can handle (guessing, again, at what the author means by "systemically overloaded").