What you have to realize is that if you live in PDT the events that are normally considered Live aren’t part of Prime Time.
All the Live sporting events (playoffs, etc) that start at or after 8PM EDT time are 5PM PDT and thus not Prime Time. Other special events such as Oscar, Tonys, Grammys, etc. are 5PM events and not Prime Time. Also other regular scheduled programs may start at 7PM PDT and are thus not Prime Time.
Plus 3 of the six major channels start their evening news at 10PM PDT and are Prime Time. But are they really Prime Time.