The Read, Unread and See All filters are no longer available. However, you can sort your emails by date, subject or sender if you switch to the Unified Inbox view.
If you’re unsure how to switch to this view, please refer to the following help article: https://help.aol.com/articles/how-do-i-switch-to-the-unified-inbox-view.Ian commented
Is AOL intentionally making their mail interface less usable? Users need BOTH a way to filter mail by subject, sender, date, etc. AND a way to filter on only unread mail. This is basic mail-server programming and for AOL to not understand that is incomprehensible. The only reasonable explanation is AOL is trying to make all of the companies mail users leave without canceling the AOL mail addresses.