All sites with pornagraphy and user generated content are now subject to age verification.
All user generated sites, mod sites, discussion forums will be forced to have stringent moderation systems in place to police speech.
Expect sites that are based outside the UK who refuse to cooperate will be fined 10% of their global turnover or a fixed fine whichever is higher or be blocked by ISPs if that doesn't work. VPNs are the only solution now should you wish to avoid handing over data.
This law is here to stay even if we have severe data breaches.
It may be modified in future but not by current government expect other countries to look at the UK as an example for their own plans.
Updated: The law is now in full effect.
Updated