He throws them open all the time with anticipation.
Look how early in the routes these balls are thrown, particularly that last one. This is throwing receivers open 101. Dak has as much arm talent as anyone, but he does not see the field like this. He just doesn't. Contrast those Goff throws to this, which is about 3 steps too late, making an easy win a tough, contested catch:
Dak can be a good QB in the right system and with the right players around him. But acting like he has the passing ability of some of the league's elite QBs, including Goff, is totally baseless. He doesn't throw with any anticipation, he has to see it first. It's difficult to throw the ball down the field in this league without that trait, and it's where the Cowboys struggle every single week.