The graphics aren't any worse than most multi-million dollar full flight simulators used for pilot training. Even better compared to some of the slightly older simulators.
The important thing is that your mind and hands go through the right motions.
(This is useful knowledge! I have trained system administrators with simulations that basically amount to pen-and-paper role-playing with some screenshots interspersed.)
That's fine for learning to fly a 737, by that time it doesn't matter much anymore. But for earlier training it's too easy, because in the real world partial visibility and light effects in clouds cause much more disorientation than zero visibility.