Earlier quoted context omitted.
That’s not really true. The Ofcom representative said “not allowed” not “unable to”. Even if cocaine is legal in my country, I’m “not allowed” to sell it to British consumers by the power of the British authorities. The British authorities may not have legal authority in my jurisdiction but they can take action in their own, including issuing penalties and stopping my deliveries at the border.
But if a Brit comes to your country and buys cocaine from you, in person, you wouldn't expect to be convicted as a dealer in the UK. Ofcom has a bad handle on web requests . Clients connect out. 4chan et al aren't pushing their services in anyone in the UK.
No? All countries catch drug dealers from other countries all the time even for the crime that happened outside of their borders. Or do you really think El Chapo could vacation freely in Europe.