Nothing is behind it. It's another dramatized thing that people are using for social media clout to score points, and people lap it up. This is manufactured rage bait.
We are also only getting one side of the story. I know for a fact a few of my breakups where the other party completely warped the story to make me into a villain. I had one incident where I was teaching my gf to snowboard and she broke her wrist on the bunny slope, a super common injury. I spent all day with her in the hospital etc. We broke up 6 months later and started telling people I had shoved her to the ground and broke her wrist on purpose because I was jealous of her success as a pianist or something and was trying to sabotage her life . It was insane and her story got worse as time went on post-breakup.
90% of these are probably just unhappy people on a bad day who are re-writing the story into some elaborate narrative of evil and abuse because they know it will do well on social media. And a lot of tiktok/social media people are very unhappy people. And unhappy people do a lot of lying and exaggerating for attention. well-adjusted people aren't making teary faced videos on tiktok about their breakups.