First, to have best view for such situation, we should see it with a bird-eye view and that image is not from a bird-eye view.
Second, if we apply technology, we should believe in it. Nothing is perfect and a semi-automated offline detection technology is not perfect but it is useful and if there are drawbacks, it will be improved in future.
They was fraction of the ball still left to cross the line for goal kick. This will be hard to see by naked eye but the chip in the Ball is helping in this situations. Because according to Adidas, the manufacturer of the ball, if the ball crosses the line and a new one is thrown then the sensor switches to that new ball. The ball been played was still showing that it was still in play when VAR checked it. Fair to say technology is causing problems but it is actually helping to correct some errors.
Even though they still have opportunities, the South Korean mission is like an impossible mission. South Korea will start the final group game against Portugal with only one point. The only thing that will lead Son Heung-min to the knock-out phase is a win against Portugal. They will have four points. And, if Uruguay can beat Ghana, La Celeste will be on par with South Korea. The team with the higher goal difference will qualify to accompany Portugal. But if Ghana and Uruguay play a draw, then South Korea will be eliminated.
With both Uruguay and South Korea levelled on same point (1) and Ghana at on 3, the permutations are;
South Korea will qualify if they win with more than two goals against Portugal and the game between Ghana and Uruguay ends in draw.
This is because FIFA doesn't count H2H. But the proceedings are
Points - GD - Goals scored - then yellows.