No need to go that far.
Your average modem user, who has found a decent ISP isn't a problem.
It's the inexcusably bad connections(this often includes broadband) that cause the problems. Living anywhere short of a 3rd world country, there is no excuse for having a ping of over 350ms, or any packetloss, ever. Anyone with an ISP who cannot offer a decent service should switch.
Broadband only is no good, since there are many areas(lots of which are urban or suburban) in the US where broadband isn't an option. I feel for those poor souls, untill a few months ago I was one of them.
The group I have no sympathy for are those with bad isps, and/or the option for broadband, who are too cheap and/or lazy to get a decent connection. Enforcing a certain quality of connection is a good idea, and I have trouble feeling sorry for those who aren't willing to invest in a decent connection. A stable 300ms ping is not really a problem. A player with a fluctuating 800ms ping, should simply be dropped by the server.