If I order something from AliExpress shipped from China, I’m importing it, and the vendor exporting it. They’re not importing it to me, and I’m not exporting it to myself.
Same thing if I make a web request for content on a server overseas.
With Alibaba it gets complicated. There are things like duty free warehouses where things can be on US soil but legally have not yet been imported. But that does not apply in the UK. 4chan does not have servers or proxies in the UK. If it did, Ofcam can go after those local entities and I would not bat an eye.
Same thing if I make a web request for content on a server overseas.