The TikTok feed is an amalgamation of posts from lots of people who aren't collaborating. The Song of Ice and Fire is a single work by a single author (or so I assume). So it's more like you're reading a single humongous post that has been “liked” (bought, positively reviewed, critically appraised) by a shitton of people, compared to a firehose of morsels that barely anyone cares about.