I am using a beamer and my TV is the whole wall on the opposite side of the living room. And as mentionned in another post, I like to have space for when I have some visits which allows having chairs around our table.

Besides not all living rooms are equals, I live in a 85m2 flat so the living room is probably much smaller than the one you would see in a typical suburbian house in the USA. And there are a lot of people living in much smaller places.

Some people just have less space. Our European standards are I would say half of the US ones so we need to save space

we don't all have TVs in our living room

Not for watching tv, but you might need the entire room for doing stretching, doing yoga or other exercises.

my apartment used to have a second bedroom, when it was 'opened up' into the living room, we used a sofa extending 'out' from the wall to separate the room

the hardest part was finding a sofa where the back wasn't just a void or some scrap fabrics