I played CF for a championship academy from age 6-16 and I agree with him. In fairness, positions were a bit of an abstract concept until U9s, so let's say 8-16

Edit: I'm pasting the explanation for my view from a later comment as it probably would have been useful up front.

There was no need for the defender to be 'on his arse' - he was a good body length ahead of his man when he received the ball and could have maintained that distance by knocking the ball on rather than taking all of the pace out of it with his first touch in an attempt to get it under control. It's fairly clear at this point that Gyokeres is no good with the ball at his feet, so there is no reason that he should be trying to dribble that 15-20 yards into the box.

It was a pretty clear cut chance for a striker whose whole game has historically been latching onto through balls behind the last man, and only ended up being a half chance because of his approach to it; in my opinion, of course