I was wondering about the "avatar" thing myself, but, looks like you and Ken answered my question. So, have to keep it the way it is.
I test the Upload a File function every once in a while to see if it's come back (as I imagine others are doing) so I can let people know. It's odd for that to break when the site speed and other functionality seem to be fine.
I wonder if the forum hosting service has decided to block uploads. I was just thinking that the Aerogarden forum does not allow uploaded images... just linked. I guess they are trying to save space on their servers or something. On that forum, avatars can be changed but no image files uploaded to posts.
With storage being so cheap, I would think that linking copyrighted material would be the greater exposure. You can save 1,000,000 one-megabyte pics on a 1 terabyte drive (a 5 terabyte drive is $130 on Amazon.) You could save over 10x as many for the size pics we generally upload. The Next Door forum only allows uploaded pics and videos. My Mazda forum is the same way.