Well of course any lag in video is going to go unnoticed anyway as long as it's constant, the only time you might notice if a program is lagging behind is if you are watching the TV while also watching what's on TV in real life (for example watching the new year countdown on a cable TV you are quite a few seconds behind real time... Before the analogue signal was cut off I always used to notice there was a good 2-3 seconds between programs on my bedroom TV and the cable living room TV) Streaming a video game requires data to be sent both ways, and is always going to be more noticeable because your actions are expected to be reflected on screen immediately, but instead you have to wait for your actions to be sent then the next frame to return (as Kynes mentioned games can have tricks that guess the next frames based on what you were doing, but sudden changes in your actions are still going to need time to register)
With a home console game... as mentioned in your graph, any lag is purely due to the hardware in front of you (console time to process your action + TV time to display)
