While I'm not a supporter of the Online Safety Bill, I do find that the opprobrium that it has inspired is consistently hyperbolic.
The Online Safety Bill bans nothing. What it does do is create a regulatory framework for the Office for Communications (aka Ofcom, HM Government's regulator for the communications industry) to operate and enforce. The regulatory framework is based around risk assessments, and sets out specific risks (of the sort that most people would agree need to be minimised). Ofcom is empowered to decide that internet services are within scope, and then demand to see policies relating to ameliorating those risks within a service.
The regulatory framework does specify that end-to-end encryption is incompatible with the reduction of these risks. However, we do have to play the ball and not the person of unspecified gender here.
We are, after all, talking about the UK here. The phenomenon of 'those whom the law protects but does not bind, and those whom the law binds but does not protect' is still very much in effect here. This legislation has also been proposed by a government that responds to increasing crime (caused by insufficient police officers) by giving those police more powers (that they don't have the resources to exercise).
Ofcom has wide-ranging responsibilities: it regulates the press and broadcast media, it allocates EM spectrum bands, it regulates the telephone network, and regulates the Royal Mail. Like all organisations in the Home Civil Service, it is staffed by a core of 'generalists' with humanities degrees, assisted by a small cadre of 'specialists', who are put back in their cupboard once they've given their opinion.
What this all means is that the bill will only have the effects that the government has said it will in its press releases. Ofcom will go after the big social media companies and the likes of 4chan. Your Mastodon server or your Gitea server or your corner of the Tildeverse or whatever will never appear on their radar. Ofcom won't have the budget or the resources to go after individuals or small communities; they won't even know you exist.
In the UK, an energy bill or council tax bill is an important identity document, necessary for opening a bank account, because any time someone starts talking about identity cards, the readers of the Daily Telegraph start muttering about the Gestapo. Ofcom isn't going to audit your homelab for online harms.