Seems like kind of a user hostile set of decisions to me, because images and screenshots are so fundamental to modern discussion… much less support.
But I suppose you are right, if all image upload file types are disabled then custom avatar should not be presented to the user as an option in the UI. Can you add that to your list @zogstrip? More of a fail safe check, if none of the common image formats are allowed, don’t allow the user to select custom avatar.
Not sure what happens when gravatar is disabled and all image file types are removed too, but I guess that is a “hey doctor it hurts when I do this” scenario…