Durant had 27 points on 11-18 shooting. Steph had 26 points on 9-18 shooting. Green had 18 points on 7-15 shooting. Klay had 11 on 5-13 shooting and was 1-6 from three... perhaps the worst performance of the 4 All-NBA players. But they put up 100 points against a top 3 team coming off a 67 win season. Nothing there suggests those guys are going to struggle to coexist offensively. They did, however, get dominated on the boards by one of the league's uniquely large teams. 55 to 35 on rebounds. They can't easily solve their size problem, but it should be noted that a lot of people felt they matched up poorly with San Antonio last year as well. Size problem isn't a problem with the vast majority of the league going small. Warriors also turned the ball over 16 times and shot an uncharacteristic 21% from three. Those are things that are understandable given it's the first real game this group has played with Durant. Even though they mesh exceptionally well, there's still a necessary adjustment period as the team shifts from having the guy in the Barnes slot go from the #4 to the #1 option.
Anyways... Spurs are a great team. Best not to read too much into the first game of a season. Remember when Pitino's Celtics won opening night against Jordan's Bulls coming off their 5th championship on their way to title 6?
So, essentially you're saying that 3 out of the 4 had great games, yet they still lost by 29 points.
Look, you can't read too much into one game, and this being the first game makes this expected. BUT it absolutely does vindicate many of the suspicions that many of us Warriors doubters have been expressing all along - 1) they're significantly worse defensively, which is very problematic; 2) they're worse in rebounding, which was already an issue to begin with; and 3) they're still (and always will be) turnover-prone due to their style of play.
If they want to have any shot of coming out of a difficult Western Conference, then they will HAVE to get better defensively, because there's pretty much nothing they're going to be able to do about their rebounding and turnover issues. They've struggled to take care of the ball their entire time together - it's just an accepted unfortunate consequence of their type of play. Further, there's not much they can do on the boards either due to their commitment to be so small.
But how they're going to become better defensively is the ultimate question, because they had to get rid of their rim protection/lane clogger/interior defense when they signed Durant. They're pretty much going to have to rely on excellent team defense (especially the utilization of help defense) and perimeter defense to get by. Green and Klay help in that regard, though Klay is very overrated at times defensively, but Curry and Durant are not necessarily known as great team defenders, especially with Curry's habit of getting beat at the top of the key often.
They'll get better in time by playing with each other, but they're going to have to get significantly better over the course of the season if they think they're getting to the Finals. Your ceiling is very limited in the playoffs if you have Swiss Cheese defense.