I disagree. It's no different from selling to a foreign buyer by sending the product in the mail. You're not doing business in their country, and it's the buyer's responsibility to adhere to their local laws about imports, not yours.
The Online Safety Act 2023[1][2][3] (OSA) (c. 50) is an act of the Parliament of the United Kingdom to regulate online content. It was passed on 26 October 2023 and gives the relevant secretary of state the power to designate, suppress, and record a wide range of online content that they deem illegal or harmful to children.[4][5]
And honestly this is more than they really should even have to do. I think it does go above their obligation. They're doing Offcom a favor here, they don't even have to figure out how to block it themselves.
And the UK... each time it delivers there.