The amazon.co.uk vs amazon.com is an example of the creeping corporate throttle-hold on trade.
Geographic separation of markets is a dream for companies - people pay different amounts in different places. I used to be able to (from here in the UK) google for example ski jacket sellers in New York; now it’s harder, and they keep changing the method. Google always tries to bend you back to UK suppliers - there’s obviously some quid pro quo between gov and Google.
So the filter here, it’s not just porn - that’s the trojan. It’s big money driving it.