> all computers must report on the identities of their users

Literally not what's happening with these bills. There is no identity, you would only have to type in a valid date (and nobody's forcing you at gunpoint to make it your actual birth date).

> The proper analogy would be require verification on the part of the porn sellers.

Red states tried that first, and it was very poorly received by the left and the porn industry, among other parties. Asking anonymously at the device level and leaving it to parents to enforce it is more privacy-respecting and less of a burden to adults. Which is exactly why blue states are now trying to do it this way (and is one of the reasons why Aylo & others have been asking for it to be done this way, with the other reason being it's also easier & cheaper on their end).