To edit the filename in the online editor, the sighted mouse user clicks to the filename in the toolbar, which makes it become editable.

However, the field is not an input until it receives focus, so a keyboard user cannot use the tab key to get to the filename and change it.

In voiceover, the user can press it, however, it is read as a heading, so the user would not know to do this. Also, the file name itself is never read.