Okay, so this scene has been talked to death on why it's bad but let's see if I can offer something new.
The moral put forth here is "overcome your individual interests for the good of all" but the most important issue with this scene is that "the good of all" does not exist. If they had accepted the premise of the mission and fought together one of them would still have been destined to fail, and thus it would be one individual putting aside their individual interests for the good of others. A sacrifice, an annoying and pervasive theme in Naruto.
But going even further we know that the failure rate for these tests is 66%
So it's more likely that only one of them would pass. That is not the "good of all" (or rather, putting the group above the individual), but in actuality sacrificing the group for the benefit of the individual.
You can defend it and say they were supposed to "look underneath the underneath" and realize that the premise for the test was false...but then nothing really matters, does it? If they figure out what Kakashi wants from them performing that action loses the authenticity of the moral; they're just giving him what he wants.
If it's "so obvious" that they're supposed to work together in a test where they are pit against each other then they're not actually putting aside their individual goals, they're all working together to accomplish their individual goals.
There is no collective goal here, nothing to prioritize above them.
But putting aside all that...why doesn't Naruto fail here? Both Sasuke and Sakura are risking their success by feeding him, but if Naruto truly prioritizes the group over his individual goals...then he should reject them. He should refuse to eat, because it's been explained to him that if his teammates feed him they "fail the test right then and there." He's sacrificing nothing, and gaining something through others sacrifice.
And yeah this is a Naruto reread so I'm gonna say it: this scene sets the tone for the rest of the series. The moral here is collective good, but "collective good" was never an outcome possible with this premise. Instead it's about an individual sacrifice for a greater "whole," where other people can only succeed if they use and discard those willing to become that sacrifice for them.
Thus...the Shinobi system.
(also suuuuuper funny their first "moral test" is about how dissent is bad. Like, this test isn't even about questioning authority. They all respect Kakashi and accept his words, it's just about being willing to suffer for the "good" of the group)
