Well you can connect any size screen, even today you can find a analog input on your huge LCD /OLED television as far as i know.
But the AV out only support a low resolution signal like TV from our childhood, so it would not scale nice to a huge screen.
Some cameras may have a HDMI and that can give you a nice HD signal, but then not all cameras can keep that signal live as well as record the signal at the same time.
But i am not sure how the market are for small screens with HDMI, larger TVs and monitors off course have it.