Product manager fail
I really would love to know who the product manager is for their broadband and sit down and have a little chat with him, sure they may have a market for the fisher price broadband, hide all the options keep the numpties from breaking it, but their 50mbit flagship product is going to attract people who actually know how to use their pc's as well they will want basic functionality.
Don't support it, thats fine we will figure it out, just don't put up road blocks.
Its band enough that they force you into using their branded hardware when any cable modem that supports the euro DOCSIS 3 standard technically could work fine on the network.