upload@mediatype and filename

In 8.1  
https://www.w3.org/community/xformsusers/wiki/XForms_2.0#The_XForms_Core_Form_Controls_Module

For <upload> it says @mediatype (xs:string) [deprecated].

Since the addition of AVTs surely this should be de-deprecated:

<upload ref="mail/attachment"
         accept="video/*,image/*,.txt,.pdf"
         label="Select attachment:"
         mediatype="{@mediatype}">
   <filename ref="@filename"/>
</upload>


It looks like filename should be an optional attribute as well.

Steven