Is using a large TV as a computer display harmful in the long term?

Saw a guy once that had a TV on the wall right behind his desk. He was using it as a computer display. Was he probably harming his health by doing that?

Should the TV be further from the eyes and then it would be ok?

Would a special TV be healthier?

Would a large computer display not make a good TV? Not watching TV that much myself but just saying.