I think now people are in their little groove and comfort zone, it's less common to just watch TV, whatever is on together. I think this makes people less tolerant. I remember being round my sisters and forced to watch strictly come dancing or the bill for example. To me these seemed to go on for days, but I didn't bitch all the way through.
My last proper boyfriend, I would ask what he wanted to watch, if he was at mine, I could veto, we would compromise . When we were at his I just watched whatever he put on, often of zero interest to me, star trek featured quite a bit. I didn't shit on his tastes, but didn't pretend to like them.
My first long term partner would really never ask my opinion on anything, wouldn't watch anything I wanted to, would even switch music if I was listening to mine. I watched stuff when he was at work. Even when we split he would always comment what I was watching when picking the kids up. I was less than polite.
As long as its give and take its fine, if you are always wrong about everything, have a bit of think. If he is just being contrary because you can't possibly be right about something, or you are insulting his dearly loved franchise.