You should be able to see everything clearly with a 50 inch screen.
But, how difficult would it be for manufacturers to create a screen function that would change a monitor to match your vision?
Let's say your vision is fine for seeing things far away but you need help with things close up.
How tough would it be to have a monitor that would allow you to push a button that would make corrections for vision that was 20/40, 20/60, 20/100?
This way you would not need to wear glasses while reading a computer screen and taking them off to see the tv across the room.
There should be a button that you push to make it 20/40 the same way you have a home button or an end button. And if someone else wants to use the computer , just 'unlock' the button.
How tough would that be to do?