Mao was useless after 1957, but he still clung on. Xi is needed to deal with Trump (likely to be re-elected), and manage relations with Putin, both of whom won't last beyond 2025. So Xi will have 3 terms max, will not last beyond 2027.
Xi has at most 10 years of active life left, especially given his years in the cave. His father also began to decline around that time.
Do you think Xi is going to be the first emperor of a new Chinese dynasty?
Going back to this.
I see this in the frame of question "Will Xi be able to purge everybody who is not happy with him before his grip starts to slip?"
The answer is obviously no. Just like Mao, he left too many "half-defeated" enemies. And the upcoming 6th generation leaders are not a candy for him either.
He obviously plans to install somebody at least as an insurance for times he can't be active due to age, and health, but also doesn't want to make himself a competitor. Xi has one such man, a present he got from Zhang Dejiang.
It's a poorly kept secret that Xi is grooming Zhong Shaojun, and possibly few other of his personal secretaries, for the role. Zhong was Zhang Dejiang's errands boy in Zhejiang, and Dejiang was a son of Zhang Zhiyi who was BFF with Peng, Ye, Wang Zhen, "old red," Yanan holdouts, and Jiang.
He served him for near 18 years, and people say that Zhong is like "dog" level loyal to Xi. And he has quite a spectacular pedigree to add to that...
He is young enough for him to be still useful at that time, and unlike Chen, he has no strings attached. Xi has managed to keep him hidden for a really long time.
A complete political eunuch, he is an ideal choice for that "insurance person" role, but no more. He will be replaced. It's said, the brass doesn't like the man either.