You can't boost pixels past the maximum amount of pixels the screen has available. You might get better colours and smoother gameplay, although without HDR you might not even see improved colours.
I'm really confused by this as the top end plazma's are still considered to produce as good a PQ than the top end 4K TVs running 4K material.
Does that mean 4K consoles won't look any better than non 4K consoles on plasma TVs?
"At a recent Shootout the ZT60 Plasma (which is slightly better than the top Pioneer Plasma's) was compared to the best TV on the market, the CZ950 Panasonic OLED. According experts the ZT60 comfortably held its own 90% of the time, exhibited better screen uniformity (particulary near black) and higher motion clarity than the CZ950"