Most TVs have quite advanced image and motion enhancement filters that have no use in a computer monitor but make a very visible difference in picture quality. I would guess scaling signals is also looked on more closely on a TV set. If your devices already do enough in this directions it is still somewhat hard to use as you have to find a way to turn the TV on. CEC is most likely not present and the only way to control it and the way its done on computers is not understood by most devices.