UK sovereign data? Land of arrests for posts on social media? Member of five eyes, "you spy on our citizens and we'll spy on yours and call it intelligence sharing"? Land of the infamous Online Safety act? That UK? Why would anyone want their data in the UK?
Did you know people live in the UK?
Just to pick on one thing, do you think incitement to murder people by setting fire to hotels, acts that subsequently happened, should just be shrugged at?
Because they reside in the UK? Why would anyone outside the US want their data in the US, the organiser and leader of the Five Eyes?
Having data processed in the UK is not for privacy reasons, but legal reasons when working in Govt. fields such as legal/healthcare/security. For privacy most companies choose juristications with better privacy laws such as switzerland.