He is actually outside the chart. According to the website (they have a handy calculator), you have to be 4 feet or closer to see all available detail on a 65 inch TV with 4k. By putting the seating back to 7 feet, he is losing benefits of the 4k resolution.That's because there are many variables to picture quality. Pixel resolution is just one, and it doesn't automatically, or magically, make picture better despite marketing claim.
You said your TV are within the chart so it's likely 4K will benefit you more than other enthusiastic people. Still, it's debatable, for example, what is better between a great 1080p plasma set which has superior black level viewing a proper authored Blu-Ray disc, or 4K set viewing 4K content streamed from website, since each side gains something and lose something. "Better" in this case will be very subjective.
It isn't as weird as you think it is since we still never believe that camera that have more pixel will be automatically better.
As you indicated, it may very well be a better TV which has added benefits, but he may be able to get many (not all) of those benefits by upscaling 1080p to 4k (depending on the upscaler). Even when they have affordable projectors, my max screen size (100 inches) will still put my seating position out of the optimum of 6 feet. So, it will be a typical "problem" for many of us. How long before people make their 8x8 rooms into media rooms? I am glad my 4k monitor is on an arm so I can put it in the perfect spot when I want to watch 4k content on my Roku 4.
All that being said, I was still surprised and disappointed that Apple didn't include 4k given the price of the new AppleTV. I still bought one because I love Airplay and was curious about the speed and apps, but I would have been happier to have some future-proofing in there, especially since iPhones already record in 4k.