They could have easily implemented the infinite scroll to enable for normal users, the new system is a complete nogo for people having to work with hundreds of photos and I thought it was a bug, until I saw they implemented it for accessability reasons. I am all for accessability, but this change is poorly thought out and cripples the functionality of Wordpress for most users. You could easily offer people the option to show a load more / infinite scroll or you could have detected screen readers automatically and then implemented this button only for users who need it. Instead you went for a huge change to the workflow without communicating it.