FYI this isn't the first time a similar extradition to the US has been denied by the UK. Lauri Love (allegedly affiliated with Anonymous) successfully fought against extradition in 2016.

Court originally ruled that extradition can happen, but the appeals court ruled differently, citing that extradition would be "oppressive by reason of his physical and mental condition".

As far as I'm aware the case never made it to the Supreme Court.