Kira's downfall in the Death Note manga occurs when his identity is exposed and he's cornered by the forces opposing him. It's a combination of smart detective work and unforeseen circumstances. His fate is both tragic and inevitable given his actions.
Honestly, we just don't know. It could potentially continue if there's enough interest and the right circumstances, but as of now, there's no definite answer.
It's been a bit challenging. The continuation without Miura has faced mixed reactions from fans, but some still hold out hope for a decent continuation.
Once upon a time, Jotaro was on a long journey. He had been traveling all day, fighting off strange creatures with his Stand. As the night fell, he found a small, cozy cave. He made a fire using some dry branches. Then, he sat down and started to think about his friends and family. The warmth of the fire made him drowsy. Slowly, he lay down, using his hat as a pillow. With the sound of the crackling fire and the wind outside, Jotaro drifted off to sleep, ready for whatever new adventures awaited him in the morning.
Jotaro was in a forest. It was getting dark. He used his Stand to find a safe place to rest. He found a large tree with a hollow at its base. He crawled inside and made himself comfortable. He thought about all the times he had been in dangerous situations. But here, in this quiet forest hollow, he felt at peace. The sounds of the forest at night, the hooting of owls and the rustling of leaves, were like a lullaby to him. He closed his eyes and soon was fast asleep, his Stand standing guard over him even in his dreams.