edit: Just to clarify. This is a good article, sorry about that. My perspective was from the content provider -- aka -- do they care if the lowest quality content is accessible via emulator generated keys.
1. It only matters to people who are used to 4K or are equipped with a 4K TV. If you don't own such screen, which a lot of people still do, it doesn't matter. You don't miss what you have never experienced.
2. When using a beamer, outright resolution is less important because the image is smoothed out. Relative to the size of my wall I don't feel like I lose detail or enjoyment on my own beamer at home than when I watch same movie in a real cinema theater. What I do miss is usually more the experience: going out, meeting friends in a neutral place and anticipate with them the screening, smelling the popcorn from the theater entrance, going out for lunch after the screening, etc. The outright resolution? couldn't care less.