Prince Muhammad bin Nayef has a reputation for ruthlessness and may not be able to amass support from the royalty and the commoners. He was loved by the Western governments for his campaign against Al Qaeda since 2003 and was offered the George Tenet medal by the C.I.A. weeks before he was dismissed as crown prince in 2015. But he also spread fear in society, detaining and torturing activists, and many Saudis suffered as he used the war on terror to silence peaceful dissent.

In contrast, Prince Mutaib’s name is not associated with repression. His power base was among the tribal groups that joined the national guard. He can live off the reputation of his father as the old patron of the kingdom. If he continues the paternalism of his father, he may become a focal symbol for rebuilding trust among his own kin.

Nobody knows for sure what the Saudi royals are thinking, but nobody would challenge King Salman if he replaces his son. Most people patronized by M.B.S. are recent appointees and should not be expected to put up a fight against King Salman.

But it is unclear if the aging King Salman fully understands that damage M.B.S. has done to the kingdom — tarnished its reputation through reckless wars, detentions, torture, and now murder, alienated the broader royal family, shattered its old consensus. Cosmetic measures — women driving, cinemas, theaters — are not enough to usher in a new dawn in the kingdom.

Although a long shot, if King Salman does replace M.B.S., he must transform the absolute Saudi monarchy into a constitutional monarchy with an elected government and parliament, who approve the appointment of future kings and crown princes. That alone will prevent the emergence of a new M.B.S.-like figure who could amass all the power and threaten the interests of the kingdom.

Saudi Arabia has had the time and the money to transform itself into a modern state that respects basic human rights and freedoms, but it has avoided that path. In the past, citizens and some royals have sought rudimentary forms of political representation but calls for constitutional monarchy have landed its proponents in prison. There is little hope of change.

King Salman will never voluntarily push for such a change without serious pressure from inside and outside the country. Given the support he has from the West, especially President Trump, most Western governments might be happy to see another abbreviation emerge as the new face of the kingdom to absorb the global outrage over Jamal Khashoggi’s disappearance and murder.