I think this is a very nice explanation that gets to the heart one of the key net neutrality issues. I would quibble with the statement "For each connection, there is someone paying money who can take their money elsewhere if that connection is too slow."

There is one person in that lineup who often can't put their money elsewhere if the connection is slow, and that's the consumer. This is the main reason that the Consumer-ISP is in the economic position to demand payment for passage through the monopoly gateway to the consumer. If the consumer could chose other access options then Consumer-ISP isn't going to be able to demand extra payment for passage.