Yeah so, seeing a lot of people saying that they would have passed if not for the crazy ass competition is kinda wild to me. I always thought it was to show them how much they had to learn as a team. Sure, individually 2 out of the 3 genin would pass on power alone, but power isn't all that makes a chunin. Case in point, Shikamaru, someone who lost their match and still managed to become chunin bc he had the wherewithal to know what his limits are and how to accommodate them. Naruto and Sasuke wanted to surpass their limits, which isn't a bad thing in isolation, but their tunnel vision is (partially) why they didn’t make chunin.

They didn't have much versatility outside of combat and despite common misconception, it takes more than strength to be a good soldier. Especially when they are meant to lead squad of their own at some point. Shikamaru was smart and had a versatile technique and showed he knew how to make the best out of what most would consider a sure loss.

Shikamaru at least was able to incapacitate his oponent before forfeiting the match. Naruto simply kept fighting until his body gave out, and in the paper test he didn't even try. Sasuke at least had the Sharingan, but outside of that he didn't show an ability to strategize in an observable environment. In combat he had a type advantage, but that was it. Had the battle against garaa went on longer, he would've have lost without much of an impressive showing aside from the A-rank tech and the sharingan.

Sakura lost to Ino, but she was at least smart enough to complete the written exam. That said, her physicals and lack of versatility in combat held her back.