OFCOM guidance is apparently forthcoming, but from reading around the Bill, my understanding is that I will be required to ensure all users are of age and further to act proactively to prevent any harmful content appearing on the pages. The consequences of not doing so could result in bankruptcy-inducing fines and/or imprisonment.
Now, obviously, this is ridiculous. This site has been running for just over twenty years (slightly miffed to have missed the anniversary in January, but there we go) in the spirit in which it is intended (notwithstanding the ever-present risk of the Morden spiral and the harm that can come from falling into one of those). So thank you all for being responsible and permitting the existence of a site that is clean, fun and requires zero moderation.
However, unfortunately, unless the guidance this is forthcoming allows the legal obligations to be performed in a light-touch and quasi-autonomous way, I don't see any alternative to pulling down the shutters and saying goodbye to this place. It's not even obvious to me that an archive of the pages can be maintained without verifying the age of anyone wanting to look at it. So archivists might want to get archiving.