Blocking acess to porn sites is as easy as setting up a firewall, my phone carrier has a feature called family shield, Google Parental Tools lets you see which websites your kid accessed, and restrict them. You do not need to ID everyone in order to let them access the internet. Did the past generations never got their hands on porn back then? Of course they did one way or another. Same with vapes or cigarettes or alcohol. There will always be a website out there that will provide free porn with no ID restriction residing in god knows where. This ID verification is useless and while it appears to be in good faith unfortunately it is not. I'd recommend watching a few videos about this such as this one from Louis Rossmann
In the end, yes there is a possibility that this won't happen, but there is a much bigger possibility that it will happen based on the track record of past bills.