Hacking a TV in 19 77

In 19 77, a broadcast of the nightly news in the u k. Got hacked by aliens. Hacking a t v would have meant hacking an entire broadcast signal. So i have to think that more than forty years after the aliens hi british t v, a hack like this might actually be easier to pull off to day. Which also seems wrong. Because if you think about it, intuitively, shouldn't technology have actually made our modern t vs more secure? We're about to find out.