Akaza was strong. Truly strong.
Although he and Kyojuro had fought to a standstill during the Mugen Train arc, in the final battle at Infinity Castle, Akaza had held his own even against both the Water Hashira, strengthened by his awakened Demon Slayer Mark, and Tanjiro, who had also awakened his mark and even entered the Transparent World. Only after a grueling struggle had they managed to cut off Akaza's head.
If Chinatsu and Kyojuro had awakened their Demon Slayer Marks now, then with the Bright Red Nichirin Swords in their hands, Chinatsu would have confidently and casually declared, "Let's rush him together and finish this quickly!" But the problem was awakening those marks...
A body temperature above 39 degrees Celsius and a heart rate above 200 beats per minute. If someone could endure the sensation of their body burning in that state, their latent potential would awaken, their physical abilities would soar, their lifespan would be capped at twenty-five, and distinctive patterns would appear on their skin. That was the Demon Slayer Mark.
Power bought with a shortened life. Honestly, Chinatsu did not want anyone in the Demon Slayer Corps to awaken a mark. Her dream was a happy ending where, after Muzan's defeat, everyone could settle down and live normal lives in peace.
In the original ending, some had died and others had been left maimed. Even with reincarnation, were they really still the same people without their memories?
Perhaps some would consider Chinatsu's wish petty, but she would firmly answer them like this.
*If I'm not going to change anything, why did I join the Demon Slayer Corps? Tanjiro and the rest of the main cast would wipe out the demons in the end anyway. It was only a few years; I could've just put up with