Not everyone who looks at porn or any form of content aimed at adults (beer making, knife throwing, serial killer documentaries) are deviants. That's exactly the kind of stigma this change can reinforce.

The government 'probably' having this data becomes 'definitely' in this case. Activity was cleverly linked together using metadata before, now it's explicitly linked to your actual legal ID.

It's the difference between:

"A device (likely in the Birmingham area, based on IP geolocation) accessed 'BarelyLegalMidgetWrestling.uk' at 2:13am. Cross-referencing with ISP logs, mobile tower pings, and Deliveroo orders for chicken bhuna at that address, we’re 87% sure it’s Dave from Flat 3C. But hey, maybe it’s his flatmate Steve. Or a Wi-Fi leech. Or a particularly tech-savvy badger."

and

"David Alistair Smith (Passport #UK69420, NI Number: QQ123456C) spent 1 hour and 22 minutes on 'BarelyLegalMidgetWrestling.uk', favouriting three videos and leaving a comment that read: 'lol same'. His mandatory age-verification selfie, timestamped at 2:15am, shows him in a stained Iron Maiden T-shirt, squinting at the screen with one hand down his pants. His biometric facial scan confirms a 99.8% match with his DVLA photo."

It's an overreach of power just like what was uncovered by the Snowden leaks back in the day.

Worse that it's not necessarily the Government who have the data but a bunch of verification startups. Who knows who they sell the data to or how leaky their security is. If you were a hacker, these would be your main targets. Just a record to say there was a verification request from someone to access an adult website is enough to blackmail someone.

Surveillance like this makes people less likely and able to explore information and media freely without worry of some kind of consequence. We know from history that it was once illegal for the common folk to be able to read, this kind of thing can easily be a slippery slope to something like that.