With respect ESB, you miss the point. The stuff Neville posts is not just tripe - which is avoidable by ignoring him - but dangerous, as he's trying to down play the destructive effects of Covid-19. By allowing him to post his uninformed pieces your forum could be seen as agreeing with what he's posting.
You do not allow racist or homophobic posts with good reason - the forum could be subject to criminal proceedings if you do. Covid-denying might be stupid but it's not against the law, which is why I assume you allow it in the interests of people expressing their views, however bizarre those views.
The forum is sailing close to the wind as a result. Neville's posts may not be illegal, but surely they should be seen as immoral and dealt with accordingly? His latest 'proof' is a piece of junk informing us that WHO are lying. It's gone too far.