I tend to not watch TV much for months at a time, then i'll rewatch something I watched years back.
My parents and girlfriends family still watch a lot of tv.
I'm currently rewatching Hannibal. I couldnt remember much aside from a vague outline of the first season so its been interesting to rewatch. I always feel like I absorb and pay more attention than I did in the past.
As for stuff I like having on in the background when relaxing, its shows like Midsummer Murders, reruns of Poirot, and ole reliables like the Top Gear Specials and Star Trek (original and TNG)
I have particularly fond memories of watching the original Star Trek series and Star Wars: The Clone Wars on saturday mornings with my dad. It was always nice to just sit there and watch something we both enjoyed. We dont really do that anymore sadly. Although there isnt really much that I watch on the TV.
I do watch gameshows like Richard Osmans House of Games with my girlfriends family, although I always find i'm worse at general knowledge things than I would like to think I am.