Is it even possible to waste time? Consider meditation. Widely considered to be a valuable and healthy activity, it literally consists of doing nothing.
Sure, when anxiety and exhaustion from your schedule stop you from doing anything productive (actual work) or healthy (meditation, walks in the park etc etc).
I don't think anyone intends anything harmful. People do harmful things because they are mistaken about stuff, including about what is good. But mistakes are a normal part of discovering the way forward, so, no, not a waste.
TV is source of background cultural knowledge and is enjoyable for that reason. When it ceases to be enjoyable one can stop watching.
OK, one might be addicted to watching TV, but that's a separate issue. Here one is using the TV to avoid addressing other problems. True, it might take a period of mindless watching in order to appreciate this. Has that time been wasted? Well, no, because it had to be spent in order to gain that very appreciation.