@Ragman,
To be honest with you, I think the main reason he lost to Liz Truss in the membership ballot is because of his race.
The party grass roots is a lot more reactionary than its MPs.
It's only party members too. We don't register as one persusion or another but we're free to join whatever party we choose.
That means members who have the vote are a lot smaller than supporters because most people don't want to bother with joining a party and paying a subscription.
Having said that Sunak is hardly representative of the immigrant experience. He's incredibly privileged, incredibly rich and went to the same schools as incredibly priviledged and rich white people.