I think I relate in different ways to different forms of drama.

Theatre is a one-off and thus I expect an emotional roller-coaster that can take me in any direction. I don't need to like the characters in theatre.

With TV, I tend to watch for different reasons. I want characters that I can empathise with. (one will do) Because a TV series is a long-term investment, I'm effectively wanting to spend time with people I can relate to.

Books likewise. I remember giving up on one Tanith Lee novel because I simply had no point of connection with the POV character.