From that BBC page it states...
'According to Ofcom, platforms must not host, share or permit content encouraging use of VPNs to get around age checks.
The government told the BBC under the Online Safety Act, it will be illegal for platforms to do this.
The regulator said parents should be aware children using a VPN to access the internet "would not be able to benefit from the protections of the Online Safety Act".
Concerned parents, it said, should block or control VPN usage.'
So this new law/ruling is because parents aren't controlling what their children are viewing who now need 'protecting'. Now they're saying the onus is back on the parents to control what and how they're using the internet.