1) he can die.
2) he can retire.
3) he can be overthrown.
as he continues to age and others begin to look past him, his abolition of term limits leaves the ambitious with no peaceful path to power, inviting them to try the third option, or at least the first.
this is the value of term limits in democratic societies but especially in undemocratic ones: they prevent revolutions of personality, by allowing for non-violent overthrow.
if xi is telling the chinese political establishment that they need to go after him to get rid of him, he very well might get it. on top of that, his successor will gain both civilian and military control. that's potentially frightening.
be careful what you wish for.