What they can likely do is the same as with porn sites: require law-abiding, trusted and well-known VPN providers to do age verification, thus pushing people to more obscure and risky providers who don’t care about the law instead.
to more obscure and risky providers who don’t care about the law instead
There’s no need to go that far, there will still be plenty of well-known and trustworthy providers who care about the law but simply operate outside of UK jurisdiction.
What they can likely do is the same as with porn sites: require law-abiding, trusted and well-known VPN providers to do age verification, thus pushing people to more obscure and risky providers who don’t care about the law instead.
There’s no need to go that far, there will still be plenty of well-known and trustworthy providers who care about the law but simply operate outside of UK jurisdiction.