Succession - part 2

Rishi Sunak has been selected as leader of the Conservative & Unionist Party and, in effect, prime minister of the United Kingdom.
He is the fifth leader since 2016's Brexit decision, the fourth to come to power without an election, the second to bypass a selection process by standing unopposed, and the third occupant of Number 10 in the past year. His immediate predecessor departs after scarcely more than one and a half months.
The rolling and interconnected issues of Brexit, the pandemic, the war in Ukraine, the energy and cost of living crises as well as the very recent and catastrophic misjudgement of the Liz Truss era and the lingering internecine conflict caused by the departure of Boris Johnson - of which Sunak was an architect - provide a challenging set of circumstances on day one of the his premiership.
Opposition parties are calling for a swift general election, stating that the new leader has no mandate from the electorate nor even the wider membership of his own party.
Sunak is the first person of colour to serve as a British prime minister. He is also the richest since the Victorian era; his personal wealth is said to far exceed that of King Charles.