These states have passed age verification laws requiring the operators of adult websites to confirm the ID of every visitor to the site. Fortunately, most of these new laws don't require us to force you to submit ID and the requirements can be satisfied using 'reasonable means', for example facial recognition software. There are several companies that have emerged recently to satisfy these requirements and we are in the process of choosing and implementing one of these companies so that we can restore access to our users in affected states asap.

Pornhub has a pretty good synopsis of the situation for those curious to know more: https://www.pornhub.com/blog/age-verification-in-the-news.