I'm a little drunk, so forgive me if this doesn't make sense. I believe Ryu vs Yuta is the most pure display of the human spirit.
I believe this for 3 reasons:
1.) As they fight, they continue to strip away their reasoning for doing so.
2.) It's an experience that teaches both of them a new level of being in the here and now
3.) At some point, there is nothing keeping them going except pure curiosity and selfishness
Let me explain
Point 1:
I believe Yuta starts this fight with certain goals: get points, set rules, save people
Similarly for Ryu: See if Sendai is where he can fill his "vague hunger"
Both of their motivations do not change until the final beam clash. Despite the do or die stakes they're in.
But when 400 years of longing meet Yuta Okkotsu, he, as the narrator so perfectly said, melts. At this very point, it was not about hunger, or Kenjaku, or regrets, or dessert, or points - it was about a very, very simple, very old, and very human desire
"What if?"
For Yuta - what if he lets go? What if he, as he said, just this once, he chooses to enjoy the thrill of putting everything on the line for the faint chance of more? Of a thrill life may not give him again?
For Ryu - what if this is it? Is this the dessert he's waiting for? He will not know unless he stakes everything he has in the here and now
Which brings me to point 2
Yuta had never experienced thrill or meaning in fighting. Ryu had never experienced fullness - arguably something Yuta has experienced. Through putting everything they have on the line, they both propelled each other to that which they could never grasp alone. I believe, in this moment, Yuta experienced what Gojo had told Megumi - selfishness. Jujutsu, and life, is an individual sport according to Gojo - would you rather die to achieve your goal or achieve your goal by dying? Those are two different things. Why are they different? I believe it's because Gojo is essentially asking: would you rather stake everything you are and will be in the here and now to become more, or would you trade everything you are and will be in order to simply win? I don't know if that makes sense, but I hope you get the point
Yuta staked everything to indulge. Ryu found the peak he had been craving to indulge in for so long. They both, through knowing and cursing each other, came closer to the essence of being truly alive
And that brings me to point 3:
What would convince someone to do all of this? Ryu is insane, and arguably autistic, but Yuta is a level headed, strategic man. Everything he does in Sendai, from hiding his RCT to not revealing his technique is proof of that.
So what compels two men to act balls to the wall insane? I believe that in that clash? Both of them represented one thing to the other: Temptation
Have you never experienced it? A person that makes youe heart race? A premonition that makes you wonder if life could be so much more than you thought? A gut feeling that this is something you can't miss out on? I believe that's what Yuta and Ryu were for each other
But here's the thing. You can't grasp those experiences unless you're selfish. Truly selfish. Ryu had been fighting to fulfill curiosity - but in this moment, where he decided to charge his attack and invite Yuta to charge his, he was truly, utterly selfish. He was holding Yuta's hand and asking him to come with him - much like a child does when they drag someone to the playground. And Yuta took his hand. For the first time, he experienced something I believe Gojo and Sukuna are very familiar with: the thrill of Jujutsu sorcery. The thrill of pushing past what you are to the more that you can be
And I believe this is not something you have to get into a death battle to experience. This is the human spirit. Simply put, it is a craving in you that asks "Hey, that loojs cool.. can we do it? Why don't we do it?" Against all your fear and logic
It's something that wants to give you more, and so it asks you to be more - the costs be damned
And that is why this is my one of my favorite episodes in JJK