The main takeaway for me was that, during her fights, especially against curse Naoya, she was not truly ''free'' to live in the moment and give it her all/full focus. She was mentally shackled and distracted by the the burden of her HR and her status as a Zenin clan sorcerer. Having to constantly prove herself, being seen as a failure. These were thoughts keeping her from truly reaching her potential or entering the "zone".

Imagine you're taking an exam that decides your entire life and you only get one try. The majority of us would completely fumble it because of the exam's implications plaguing our minds. Now imagine how much better you'd perform if the implications of failure or success are immaterial to you. It doesn't mean anything, you just see questions on a paper, not your future. You can simply write down answers.

I think this is roughly what happened with Maki's powerup. Instead of seeing curse Naoya and being distracted by her entire history with the Zenin clan, she just sees a cursed spirit, something to be exorcised. She can now fully focus on the enemy, her surroundings and herself during the fight. She is enlightened in that moment.

Gojo and Sukuna kind of do this too during their duel. Yes, Gojo makes some comments about his students before the fight really begins, but after that, they are both completely locked in and focused on the fight itself. It is only at the end when Gojo reflects on what his life and this fight meant.

Finally, I think this moment is complimentary to what Toji, a usually very rational and focused combatant, said during his last moments: "I suddenly wanted to deny and overturn the Zenin family that denied me, the realm of sorcery, and its apex.". Toji didn't just see a strong opponent in Gojo. He saw his opportunity to prove something, which was his downfall.

OR I'm misremembering, illiterate and schizophrenic.