In my opinion, posts with the #steemexclusive hashtag mean that the text and photos are being published on Steemit for the first time. I believe that after publication, every author has the right to continue publishing content on other platforms.

Although the term "exclusive" itself implies uniqueness. At the time of publication, this is true. However, plagiarism is widespread online, and others can use your photos or text without the author's permission. I periodically find my photos on other platforms, published by others in their own name without my permission.

So why not give the author who first published unique material on Steemit the right to continue using it as they see fit.