So, what makes the UK Online Safety Act close the forum?
Children's access assessments - 32 pages
Guidance on highly effective age assurance and other Part 5 duties - 50 pages
Protecting people from illegal harms online - 84 pages
Illegal content Codes of Practice for user-to-user services - 84 pages
I look forward to reading your fully compliant risk assessment before interacting with this comment, lest it be judged to contain offensive, inappropriate, or pornographic content.
The costs required to operate any website covered by this act (which is effectively all websites) is grossly excessive and there are either NO exceptions, or the UK has refused to explain who is excepted.
That depends what you count as the costs. If you're a small site[0] and go through the risk assessment[1], that's the only costs you have (unless pornography is involved in which case yes, you'll need the age verification bits.)
[0] ie. you don't have millions of users
[1] Assuming Ofcom aren't being deliberately misleading here.