I don't get your argument. You seem to be saying that if the internet-only plan is made too expensive then customers will subscribe to the not very much more expensive TV+internet plan. Isn't that what they want customers to do?
So you're proposing there is no TV+internet package available from the ISP, they offer only internet and you get your TV from someone like Netflix.
If the ISPs at this point charge a price for just internet service that makes offering that service profitable, what are you expecting customers to do? Go without internet service?