Two free kicks spring to mind:
1) Robert Huth’s tremendous feck up a few years ago.
2) Maddison against Southampton a couple of weeks ago.
Very similar positions, with very different people taking them. Their xG would be about the same, as the situation was not far off identical and, yet, they yielded very different results. Isn’t that strange? How could that possible be? Could it maybe have something to do with who the chance falls to?
That article actually highlights the flaws within it. Everton’s attackers score closer to their xG than their midfielders and, even more so, their defenders. Who’d have thought that eh? xG takes no account for goalkeeping errors, who’d have thought that may affect whether a goal is scored?
The article doesn’t make the case for xG, it does quite the opposite, whatever it’s intentions were.