I'm yet to read any convincing account about how, if we got there, Leninists would start to break down the vehicle they used to defeat capitalism and rallied society around.
Lenin himself writes extensively on critiquing the existence of the state, so any real leninist would align with this position. Mao himself also was quite anti-state, see the cultural revolution. Both of these incredibly important figures were anti state but saw it as a necessary tool to defend against extreme capitalist agression. there is little doubt in my mind that if capitalism fell, many would start critquing and deconstructing the current power structures.
Many would see it in their best interest too, because every head of Marxism leninism has shouted to the stars about the bureaucratic state apparatus corrupting Socialism and causing capitalist restoration.