Broadcast TV has been dying for 20 years, cinema has been dying for around 50 years. 
Broadcast TV is probably going to be around as a major player for quite a long time (multiple decades), as it's cheap to run per viewer, easy to implement and maintain (one transmitter per X tens of thousands or millions of users), and scales up extremely well with no additional cost per user (for the output) from 1 to 10,000,000 if they're within range of the transmitter.
Internet services will likely still be struggling to provide enough bandwidth for all properties covered by Broadcast TV in 10-20 years for one channel at a time, let alone multiple channels at once (especially if the definition of the content increases).

Broadcast TV is probably going to be around as a major player for quite a long time (multiple decades), as it's cheap to run per viewer, easy to implement and maintain (one transmitter per X tens of thousands or millions of users), and scales up extremely well with no additional cost per user (for the output) from 1 to 10,000,000 if they're within range of the transmitter.
Internet services will likely still be struggling to provide enough bandwidth for all properties covered by Broadcast TV in 10-20 years for one channel at a time, let alone multiple channels at once (especially if the definition of the content increases).