This is not really about compliance. They license their content from their media partners and these licensing agreements state in which territories they are all

This is not really about compliance. They license their content from their media partners and these licensing agreements state in which territories they are allowed to use the licensed content. Their media partners are contractually requiring them to take steps to block the usage of their content outside the licensed territories. Keep in mind that the party who has licensed Netflix a production to be used in e.g. the US might not even have the rights to the same production in e.g. the UK.