Because all genocides are committed by the government and the first step in that process is tracking everyone. They claim they are protecting you from "criminals", but it is governments that have murdered in excess of 500 million people in the last 100 years for various agendas that generally boil down to "you don't follow our rules (not the correct fascist/Communist/Imperial) or you aren't the right race so you must be eliminated". Also, a significant number of them simply lust for innocent blood and carnage. Hence, genocide after genocide and Epstein's Islands.

Edit: and they always seek the powers needed under various forms of the mantra of "for your safety".

Not to steal u/Mrexreturns thunder, but I think age verification will lead to digital biometric verification (probably iris reading) which will also go into a type of social credit scoring and eventually some biblical stuff like not being able to buy or sell without the mark of the beast and those not 'in the club' are gonna be hunted and murdered, probably beheading.

I also think there will be an actual angel warning not to take 'the eventual mark' and it incorporates an aspect of worship and cannot be taken by accident.

It's boiling frogs stuff.

The goal of this particular stepping stone towards globalism and mass deaths is to make everything digital (including life-critical systems) and block access to anyone who doesn't provide real-world identity verification.

And 'real-world-identification' gets more extreme each year.
Started with receiving a code to E-mail.
Then a code to a second 'recovery' E-mail.
Then a code to your phone.
Then a picture of a photo ID.
Then a picture of you holding the ID.
Then you holding two forms of ID.
Then a 5-second selfie video of you holding the ID's.

Each time the people comply, they move onto the next stage.

Biometrics, retinal scans, & implants have arrived.
DNA reading devices come after that.

One of the lessons from the COVID19 test was to determine how the population would respond to ridiculous government demands and, in particular, how long they could sustainably make those demands.

Armed with this information they've realized that locking down communications channels for "dissenters" is going to be key to keeping the compliance rate particularly high. Which will be necessary for their "15 minute cities" dream.

They've done their research here as they've realized that this requirement will most likely be flatly rejected precisely by the group they ultimately want to target with it, yet be flowery enough that NPCs will comply without question. You should note these age verification laws appearing at state and federal levels globally all at nearly the same time and all using the same languge.

The law is a tool which naturally expands itself. You'll also notice these laws are written so poorly that if they ever are adjudicated they could be construed to mean almost anything. The US First Amendment is the only bulwark but that will take 10 to 12 years to get fully settled through the Supreme Court. Which is more than enough time to meet their next most immediate goal.

Penning humanity into cages.

The Hutus in Rwanda 1994 didn't just kill strangers; they know who to get rid very well.

Point is that if the Globalists have your personal information and your browsing/gaming/chatting history, the Antifa/Neo Nazi murder warlords or the Globalist commune leaders will find a way to get you killed.