Will anyone still watch broadcast TV?
Yes, I rather suspect they will. There will still be the old fogeys like me who can cope with waiting for next week's exciting episode; who don't want to watch the entire series in one hit; who don't really care about the latest series of whatever, only available in the states. They're the people who in general trust the taste of the programme makers and channel directors; the people (like me!) who listen to 'Radio 4' rather than 'talk radio'.
And they'll probably still prefer to record the commercial channels and skip through the adverts.