The arrow is correct, if the picture is relative to the ball's initial velocity. Relative to the ball's initial velocity, the air will blow it downwards and to the right, which matches the path shown.I had posted the picture for what seemed to me like gross inaccuracy. But upon closer inspection, if the arrow in "path of the ball" is reversed, the situation may be restored.
As I posted in the other thread regarding spinning ping pong ball and it's curved path, I've never like using "Bernoulli" effect to explain lift. I prefer the Newton explanation that air is accelerated and responds with a reactive force, and it's clear that work is being done on the air. The Bernoulli effect methods sometimes ignore the fact that work is being done on the air. It's not the horizontal airflow that causes lift, it's the downwards acceleration of air.But why did you say that the Bernoulli reference was misleading?