WhY?
this whole argument is silly there already an open standard for cable boxes, it called OCAP, stands for Open Cable Application Platform, it been around since 2007. most cable providers already have the ability to add custom equipment, also based on the standard was Tru2Way, which was a cable card that could support all the features a set top box does, problem no TV manufacturer except Panasonic used it, because they burned themselves releasing cablecard 1.0 before the standard was ratified, which they lost a lot of money on it when the standard changed right before it released.
Similar issues with cable boxes there is nothing to prevent any manufacturer from making a box for retail sale, everything already supports it. The reason the haven't is 2 fold: 1 they don't have the production capacity to supply catv providers with boxes and the retail market. 2. the few that could dont have any incentive, they already have a steady vertical market, without having to deal with wholesalers etc.there is also not enough demand for it to be worth the trouble.
The reason catv providers are suing is the fcc wants a new standard for boxes that doesnt do anything that the current standard doesnt already, this would cost billions for no gain from what is already there.