There are all kinds of digital copyright issues, that lawyers make them block certain things. I used to be able to Chromecast the ESPN app, but an update took that feature away. I can use a cable on my old iPad to watch ESPN on the TV, but it will not work with my newer iPhone.
Also one thing I've found is that many campgrounds we go to you have enough cell data bandwidth to read the news, and emai, but not to stream HD tv.
Really the best bet is satellite. I don't do it because I work for a small cable company and get cable for free, but if I was paying, I'd get a dish for camping.