That exact question is addressed almost word-for-word in TFA:
You are probably now thinking something along the lines of "My couch is 10' away from my TV, which according to the chart means I need a 75 inch TV. This is insane!". Yes, if you want to take advantage of the full capacity of higher resolutions, this is the ideal size. This brings us to the main limitation for most people: the budget.
The price of a TV is exponential to its size, as shown in the chart. The chart shows the price range of 2016 LED TVs by their size. As you can see, the jump to a 70 inch TV is quite a big one. For example, check out the price of our picks for the best 70"-75" TVs and the best 80-82-85" TVs.
Conclusion
We recommend an angle of vision of 30 degrees for a mixed usage. In general, we also recommend getting a 4k TV since 1080p choices have become quite limited and lack modern features such as HDR. To easily find out what size you should buy, you can divide your TV viewing distance (in inches) by 1.6 (or use our TV size calculator above) which roughly equals to a 30 degrees angle. If the best size is outside your budget, just get the biggest TV you can afford.
Except that, though I can afford a bigger tv than 55" tv, I still am not going to buy one. And buying the 85" they recommend is _enormous_. It might make for a cinematic experience, but it poses additional problems beyond price:
1) You can never sit closer to the TV. I always sit ~12' from my TV, but walking by the tv at close range (between two doors on either side) is going to be jarring for passers-by. If I have friends over for a movie night, we would have to huddle at the far end of the room.
2) It doesn't fit the space, both physically and design wise. I couldn't put that big a tv in the space if I wanted. Even if I did, it's going to be ugly as sin unless the space is very specifically designed for cinema experiences.
3) That's going to be an obnoxious way to watch non-cinema content.
Having a TV at the other end of a 12 foot room is not going to be an uncommon affair. Having a room where an 85" screen is appropriate is another matter all together.
I feel like the article should have a big disclaimer at the top "This is the maximum size you can enjoy, not the maximum size you should necessarily buy".
It really isn't. This quote is just saying that you probably can't afford the size of TV they're going to recommend, so you should "just get the biggest TV you can afford."
You are probably now thinking something along the lines of "My couch is 10' away from my TV, which according to the chart means I need a 75 inch TV. This is insane!". Yes, if you want to take advantage of the full capacity of higher resolutions, this is the ideal size. This brings us to the main limitation for most people: the budget.
The price of a TV is exponential to its size, as shown in the chart. The chart shows the price range of 2016 LED TVs by their size. As you can see, the jump to a 70 inch TV is quite a big one. For example, check out the price of our picks for the best 70"-75" TVs and the best 80-82-85" TVs. Conclusion
We recommend an angle of vision of 30 degrees for a mixed usage. In general, we also recommend getting a 4k TV since 1080p choices have become quite limited and lack modern features such as HDR. To easily find out what size you should buy, you can divide your TV viewing distance (in inches) by 1.6 (or use our TV size calculator above) which roughly equals to a 30 degrees angle. If the best size is outside your budget, just get the biggest TV you can afford.