A social media site typically takes a soft licence allowing it to store and reproduce your content (which is needed to be able to function), and maybe use it in marketing. Some go a little further, but please show me one mainstream site that takes over all your (copy)rights when you post?
You might be correct that I'm mistaken wrt the intellectual property of comments. I'm not an IP lawyer and cannot state it with confidence one way or another.
What I feel comfortable stating is however that we have precident for the exact scenario the person I responded to (wanting royalties for a storyline they posted on a social media website) and this precident showed that are least the lawyers of WB were of the opinion that a rewrite outside of any social media platform was necessary.
A social media site typically takes a soft licence allowing it to store and reproduce your content (which is needed to be able to function), and maybe use it in marketing. Some go a little further, but please show me one mainstream site that takes over all your (copy)rights when you post?