DA
the sentence you quote is standard to most (all?) sites that allow you to upload images as resizing your image from, for example, 350x350 dragon image to 50x50 lair view, falls under that sentence; there should be a separate point about who owns the intellectual property, ie who and where and how someone is allowed to sell the image. example: tumblr tos https://www.tumblr.com/policy/en/terms-of-service