If dak can't throw, how do you explain 2016?
If zeke was a crutch for dak in 2016, how do you explain week 1?
This is a NFL thing.
I am following the league for a long time now and what you can recognize is that teams need around 1 season to find out about the strengths and weaknesses of a new QB.
A good example in the past is Colin Kaepernick.
Especially at the QB position the NFL is all about finding strengths and weaknesses. After opposing DCs found them they will take away your strengths and let them beat you by your weaknesses.
In Daks case thats his accuracy and his reading process. He is not able to deliver the long ball precisely and he needs too much time to go thru his progressions. He doesnt handle the pocket well. He is not good when passing on the run (he is good when rolling out to the left but he misses passes when running to the right or foward).
So teams in 2017 took away the short field. That also helped against the strong running game Dallas has. They took away his first receiving target (not Dez but Beasley) They gave him the long field. Dak wasnt able to handle that kind of scheme.
This is how the game in the NFL works. You are strong in some areas as a QB. DCs will take them away. Now its up to the player and his talent level if he can work on his weaknesses and make them strengths too. Then and only then he will establish himself as a good QB. Thats the situation Dak is in right now. And to be honest it doesnt look like he has the talent to overcome his weaknesses.
Lets wait 7 or 8 more games. Especially at the QB position i like Parcells way to give players 3 years before judging hem. But the last season showed it already. And he doesnt look promising after the first game this year. He had a whole offseason to work on it. And TBH he looks like last year.