Hmm, to me there are two questions here. Is Britain racist, and is that the cause of Sunak not being in the lead in the leadership contest.
To answer the first, yes of course there are still elements of it. Institutional racism and individual. Unfortunately, though the individual racism comes from all quarters. My daughter is really good friends with an Asian girl who has to pretend to see my daughter because her parents won't let her hang out with the white girl as she'll lead her astray. She's not allowed to come here on sleepovers (only to other Asian houses), or even for socialising. My daughter is only allowed there to study, and only when the parents are around. So yes, racism is very much alive and in all quarters.
As for the Sunak question, he would be my choice to be pm, but I do think there are some big reasons why he won't,
Whilst you're right Truss went to Oxford, she also went to state comprehensive school. For some, who have had enough of the Rich Toryboy image (Johnson, Cameron), she will appeal and may be seen to have wider appeal outside of the party for that reason.
His money is seen as problematic as well as the non dom status of his wife, his green card status etc. Some feel he and his wife played the system, her claiming non dom whilst living in number 11 and sending their kids to a British school.
I agree with the points namechange made up thread. Truss says a lot more right thing things and models herself on Thatcher, which will appeal, even if it in not honest or good for the country,
But I think Sunak's biggest problem is that he is seen to have stabbed Johnson in the back, and many of the party faithful bizarrely still really liked Boris,