What DNA tests demonstrate is that except for politics there is no "them" and "us".
I would not be surprised to learn that everyone with Mayflower ancestry also runs on at least some Native-American and African-American and South American DNA.
In Australia, my understanding is that 75% of people First Fleet ancestry have at least some indigenous DNA and that 100% of Australians identifying as indigenous also carry indigenous DNA.
Because a mother only gives 1 of her 2 chromosomes to her baby, ancestry DNA links invariably get broken. A boy will not for example share any DNA with his father's mother.
And so it goes on ……. but the bottom line is that the pot is already well mixed.
If the worst dirt the far-right can dig up on Elizabeth is a dodgy Ancestry DNA kit test then so be it. Let's run with that one guys.