I agree, they are not ethnically English, they are British citizens and have all the rights that come with citizenship, the same as every other UK citizen including those that would call themselves English. You think there's some kind of gotcha there, but there isn't.

England hasn't had an English king since 1066, that's not controversial, and even then the inbreeding between the European royal houses was creating a pan-european elite that made world world 1 more of a really bad family argument than anything else.

What's really odd is that Rishi Sunak is extremely proud of his ethnicity and heritage, it's unfortunate that we've made it almost impossible for other people's to have that same pride.